Sample Chapter

INSTANT DOWNLOAD COMPLETE TEST BANK WITH ANSWERS

 

 

Test Bank Of College Physics A Strategic Approach 2nd Edition by Knight

 

 

 

SAMPLE QUESTIONS

 

College Physics, 2e (Knight)

Chapter 1   Representing Motion

 

1.1   Quantitative

 

1) The following conversion equivalents are given:

1 gal = 231 in3      1 ft = 12 in      1 min = 60 s

A pipe delivers water at the rate of  95 gal/min.  The rate, in in3/s, is closest to:

  1. A) 0.21
  2. B) 0.19
  3. C) 0.17
  4. D) 0.15
  5. E) 0.14

Answer:  A

Var: 50+

 

2) The following conversion equivalents are given:

1 m = 100 cm    1 in = 2.54 cm      1 ft = 12 in

A bin has a volume of 1.5 m3.  The volume of the bin, in ft3, is closest to:

  1. A) 35
  2. B) 41
  3. C) 47
  4. D) 53
  5. E) 59

Answer:  D

Var: 1

 

3) The following conversion equivalents are given:

1 mile = 5280 ft      1 ft = 12 in     1 m = 39.37 in      1 hour = 60 min     1 min = 60 s

A particle has a velocity of  4.7 miles per hour.  The velocity, in m/s, is closest to:

  1. A) 2.1
  2. B) 1.7
  3. C) 1.9
  4. D) 2.3
  5. E) 2.5

Answer:  A

Var: 50+

4) The following conversion equivalents are given:

1 kg = 1000g      1 l = 1000 cm3         1 l = 0.0353 ft3

The density of a liquid is  0.83 g/cm3.  The density of the liquid, in kg/ft3, is closest to:

  1. A) 24
  2. B) 19
  3. C) 21
  4. D) 26
  5. E) 28

Answer:  A

Var: 50+

 

5) A weight lifter can bench press 171 kg. How many milligrams (mg) is this?

  1. A) 1.71 × 108mg
  2. B) 1.71 × 109mg
  3. C) 1.71 × 107mg
  4. D) 1.71 × 106mg

Answer:  A

Var: 50+

 

6) How many nanoseconds does it take for a computer to perform one calculation if it performs

6.7 × 107   ?

  1. A) 15 ns
  2. B) 67 ns
  3. C) 11 ns
  4. D) 65 ns

Answer:  A

Var: 50+

 

7) A CD-ROM disk can store approximately 600.0 megabytes of information. If an average word requires 9.0 bytes of storage, how many words can be stored on one disk?

  1. A) 6.7 × 107words
  2. B) 5.4 × 109words
  3. C) 2.1 × 107words
  4. D) 2.0 × 109words

Answer:  A

Var: 9

8) Your car gets 34.7 mi/gal on a trip. How many kilometers/liter did it get? (3.79 = 1 gal; 1 mi = 1.61 km)

  1. A) 14.7 km/l
  2. B) 9.16 km/l
  3. C) 55.9 km/l
  4. D) 32.4 km/l

Answer:  A

Var: 50+

 

9) The wavelength of a certain laser is 0.66 microns, where 1 micron = 1 x 10-6 m. What is this wavelength in nanometers? (1 nm = 10-9m)

  1. A) 6.6 × 102nm
  2. B) 6.6 × 103nm
  3. C) 6.6 × 101nm
  4. D) 6.6 × 104nm

Answer:  A

Var: 50+

 

10) Express [ 2.2 × 106]-1/2 in scientific notation.

  1. A) 6.7 × 10-4
  2. B) 1.5 × 103
  3. C) 1.5 × 10-5
  4. D) 1.5 × 104

Answer:  A

Var: 40

 

11) An oak tree was planted 22 years ago. How many seconds does this correspond to? (Do not take leap days into account.)

  1. A) 6.9 × 108
  2. B) 1.2 × 107
  3. C) 2.9 × 107
  4. D) 2.8 × 108

Answer:  A

Var: 12

12) A plot of land contains 5.8 acres. How many square meters does it contain? [1 acre = 43,560 ft2.]

  1. A) 2.3 × 104m2
  2. B) 7.1 × 103m2
  3. C) 7.0 × 104m2
  4. D) 5.0 × 104m2

Answer:  A

Var: 50+

 

13) A person on a diet loses 1.6 kg in a week. How many micrograms/second (µg/s) are lost?

  1. A) 2.6 × 103μg/s
  2. B) 1.6 × 105μg/s
  3. C) 44 μg/s
  4. D) 6.4 × 104μg/s

Answer:  A

Var: 11

 

14) Which of the following is a reasonable estimate of the number of characters (typed letters or numbers) in a 609 page book? Assume an average of 194 words/page and a reasonable average number of letters/word.

  1. A) 5 × 105char
  2. B) 5 × 107char
  3. C) 5 × 106 char
  4. D) 5 × 104char

Answer:  A

Var: 50+

 

 

15) Add 3685 g and 66.8 kg and express your answer in milligrams (mg).

  1. A) 7.05 × 107mg
  2. B) 7.05 × 104mg
  3. C) 7.05 × 105mg
  4. D) 7.05 × 106mg

Answer:  A

Var: 50+

16) What is  to the proper number of significant figures?

  1. A) 0.91
  2. B) 0.911
  3. C) 0.9108
  4. D) 0.9

Answer:  A

Var: 50+

 

17) An equation that you will use later is x = at2, where a has units of acceleration, t has units of time, and x has units of distance. If t = 61.9 s, find the difference between the values of x obtained when a = 9.81 m/s2 and when a = 10.0 m/s2.

  1. A) 4 × 102m
  2. B) 3 × 102m
  3. C) 6 × 102m
  4. D) 1 × 103 m

Answer:  A

Var: 50+

 

18) What is 0.2052/3, to the proper number of significant figures?

  1. A) 0.348
  2. B) 0.35
  3. C) 0.3
  4. D) 0.3477

Answer:  A

Var: 50+

 

19) A marathon is 26 mi and 385 yd long. Estimate how many strides would be required to run a marathon. Assume a reasonable value for the average number of feet/stride.

  1. A) 4.5 × 104strides
  2. B) 4.5 × 103strides
  3. C) 4.5 × 105strides
  4. D) 4.5 × 106strides

Answer:  A

Var: 1

 

20) Estimate the number of times an average person’s heart beats in a lifetime. Assume the average heart rate is 69 beats/min and a life span of 75 yr.

  1. A) 3 × 109beats
  2. B) 3 × 108beats
  3. C) 3 × 1010beats
  4. D) 3 × 107beats

Answer:  A

Var: 50+

 

1.2   True/False

 

1) The change in the position vector of a moving object is equal to the distance it has moved.

Answer:  FALSE

Var: 1

 

2) If a vector pointing to the right has a positive magnitude, then one pointing to the left has a negative magnitude.

Answer:  FALSE

Var: 1

 

3) If a bird is moving at 3.5 m/s at a certain instant of time, then it will travel 3.5 m in the next second.

Answer:  FALSE

Var: 1

 

4) If the final position vector of a moving object has a smaller magnitude than the initial position vector, then the change in the object’s position vector has a positive magnitude.

Answer:  TRUE

Var: 1

 

5) Since vectors always have positive magnitudes, the sum of two vectors must have a magnitude greater than the magnitude of either one of them.

Answer:  FALSE

Var: 1

 

6) If the average speed of an object is zero, then its average velocity must be zero; but if its average velocity is zero, its average speed is not necessarily zero.

Answer:  TRUE

Var: 1

 

1.3   Conceptual

 

1) The length of a certain piece of wood is stated as 12.946 cm. Thinking in terms of accuracy and significant figures, what value would you obtain if you measured this board with a ruler whose smallest division is the millimeter?

Answer:  Since 1 cm = 10 mm, you could only measure this board to 1/10 of a centimeter, therefore, 12.9 cm.

Var: 1

 

2) A possible unit for the measure of time would be the period of your own pulse. Why might this unit not be a good choice for a time standard?

Answer:  In general, the human pulse rate often changes. Also, other people would, in general, have different pulse rates, so it would be difficult to reproduce the standard.

Var: 1

 

3) What are some advantages of using scientific notation to express very large or very small numbers?

Answer:  The main advantage is the ability to express these numbers in a minimum amount of space. For example:

1 trillion = 1,000,000,000,000

= 1 × 1012

Var: 1

 

4) If you needed to estimate the number of gallons of gasoline burned in the United States each year by automobiles, what quantities would you need to assume? What formula would you need to use?

Answer:  If you assumed

N = total number of cars

M = average number of miles driven each year per car

R = average number of miles per gallon

Then

Total number of gallons =

Var: 1

 

College Physics, 2e (Knight)

Chapter 3   Vectors and Motion in Two Dimensions

 

3.1   Quantitative

 

1) The components of vectors  and  are given as follows:

 

Bx =  -9.2        Cx =  -4.5

By  =  -6.1       Cy = + 4.3

 

The angle (less than 180 degrees) between vectors  and , in degrees, is closest to:

  1. A) 77
  2. B) 103
  3. C) 10
  4. D) 170
  5. E) 84

Answer:  A

Var: 50+

 

2) The magnitude of  is  5.5. Vector  lies in the second quadrant and forms an angle of 34 degrees with the y-axis. The components, Ax and Ay, are closest to:

  1. A) Ax= – 3.1, Ay = + 4.6
  2. B) Ax= + 3.1, Ay = – 4.6
  3. C) Ax= + 4.6, Ay = – 3.1
  4. D) Ax= – 4.6, Ay = + 3.1
  5. E) Ax= – 4.6, Ay = – 3.1

Answer:  A

Var: 50+

 

3) A hiker walks 6.7 miles to the east in 5.1 hours then turns around and walks 1.1 miles to the west in 1.0 hours. What was her average velocity during the trip?

  1. A) 0.92 mph
  2. B) 1.3 mph
  3. C) 1.2 mph
  4. D) 3.9 mph

Answer:  A

Var: 50+

 

4) Vector  has length  4 units and directed to the north. Vector  has length 9 units and is directed to the south. Calculate the magnitude and direction of  + .

  1. A) 5 units, south
  2. B) 5 units, north
  3. C) 13 units, north
  4. D) 13 units, south

Answer:  A

Var: 20

 

5) You walk 55 m to the north, then turn 60° to your right and walk another 45 m. How far are you from where you originally started?

  1. A) 87 m
  2. B) 50 m
  3. C) 94 m
  4. D) 46 m

Answer:  A

Var: 31

 

6) You walk 53 m to the north, then turn 60° to your right and walk another 45 m. Determine the direction of your displacement vector. Express your answer as an angle relative to east.

  1. A) 63° N of E
  2. B) 50° N of E
  3. C) 57° N of E
  4. D) 69° N of E

Answer:  A

Var: 50+

 

7) Vector  points to the north and has length A. Vector  points to the east and has length

B = 2.0 A.  Find the magnitude of  = 4  +  in terms of A.

  1. A) 4.5A
  2. B) 6A
  3. C) 3.6A
  4. D) 3.1A

Answer:  A

Var: 50+

8) Vector  points to the north and has length A. Vector  points to the east and has length

B = 2.5A.  Find the direction of  = 7.4  + . Express your answer as an angle relative to east.

  1. A) 71° north of east
  2. B) 19° north of east
  3. C) 82° north of east
  4. D) 60° north of east

Answer:  A

Var: 50+

 

 

9) A rabbit trying to escape a fox runs north for 8.0 m, darts northwest for 1.0 m, then drops

1.0 m down a hole into its burrow. What is the magnitude of the net displacement of the rabbit?

  1. A) 8.8 m
  2. B) 8.1 m
  3. C) 66 m
  4. D) 10 m

Answer:  A

Var: 50+

 

10) Karim rides his bike with velocity  = ( 8.4 m/s, 25° north of east) for 10 minutes. How far to the north of his starting position does Karim end up?

  1. A) 2100 m
  2. B) 4600 m
  3. C) 76 m
  4. D) 36 m

Answer:  A

Var: 50+

 

11) Jordan ran up the hill at 7.0 m/s. The horizontal component of Jordan’s velocity vector was  1.8 m/s. What was the angle of the hill?

  1. A) 75 degrees
  2. B) 57 degrees
  3. C) 33 degrees
  4. D) 15 degrees

Answer:  A

Var: 47

12) Jeff ran up the hill at 7.0 m/s. The horizontal component of Jeff’s velocity vector was

5.1 m/s. What was the vertical component of  Jeff’s velocity?

  1. A) 4.8 m/s
  2. B) 4.3 m/s
  3. C) 3.8 m/s
  4. D) 3.4 m/s

Answer:  A

Var: 50+

 

 

 

 

13) A projectile is fired from  the origin (at y = 0 m)  as shown in the figure. The initial velocity components are vox = 940 m/s and voy = 96 m/s. The projectile reaches maximum height at point P, then it falls and strikes the ground at point Q. In the figure, the y-coordinate of point P is closest to:

  1. A) 470 m
  2. B) 45,550 m
  3. C) 45,080 m
  4. D) 940 m
  5. E) 90,160 m

Answer:  A

Var: 1

14) A projectile is fired at time t = 0.0 s, from point 0 at the edge of a cliff, with initial velocity components of vox = 30 m/s and voy =300 m/s. The projectile rises, then falls into the sea at point P. The time of flight of the projectile is 75.0 s.

 

 

 

In the figure, the horizontal distance D is closest to:

  1. A) 2250 m
  2. B) 2520 m
  3. C) 2790 m
  4. D) 3060 m
  5. E) 3330 m

Answer:  A

Var: 50+

 

15) A projectile is fired at time t = 0.0 s, from point 0 at the edge of a cliff, with initial velocity components of vox = 50 m/s and voy =200 m/s. The projectile rises, then falls into the sea at point P. The time of flight of the projectile is 50.0 s.

 

 

 

In the figure, the y-coordinate of the projectile when its x-coordinate is  1000 m is closest to:

  1. A) + 2040 m
  2. B) 150 m
  3. C) – 150 m
  4. D) + 1240 m
  5. E) + 600 m

Answer:  A

Var: 50+

 

16) An apple falls straight down from an apple tree growing on a 20° slope. The apple hits the ground with a speed of  16.2 m/s. What is the component of the apple’s impact velocity parallel to the ground?

  1. A) 5.5 m/s
  2. B) 8.7 m/s
  3. C) 12 m/s
  4. D) 15 m/s

Answer:  A

Var: 50+

 

17) A rescue plane spots a survivor 132 m directly below and releases an emergency kit with a parachute. If the package descends at a constant vertical acceleration of 6.89 m/s2 and the initial plane horizontal speed was 68.9 m/s, how far away from the survivor will it hit the waves?

  1. A) 426 m
  2. B) 2.64 km
  3. C) 301 m
  4. D) 446 m

Answer:  A

Var: 50+

 

18) A boy throws a rock with an initial velocity of 3.13 m/s at 30.0° above the horizontal. How long does it take for the rock to reach the maximum height of its trajectory?

  1. A) 0.160 s
  2. B) 0.282 s
  3. C) 0.313 s
  4. D) 0.441 s

Answer:  A

Var: 50+

 

19) A cat leaps to catch a bird. If the cat’s jump was at 60.0° off the ground and its initial velocity was 2.74 m/s, what is the highest point of its trajectory?

  1. A) 0.29 m
  2. B) 0.58 m
  3. C) 10.96 m
  4. D) 0.19 m

Answer:  A

Var: 50+

 

20) A football kicker is attempting a field goal from 44 m out. The ball is kicked and just clears the lower bar with a time of flight of 2.9 s.  If the angle of the kick was 45°, what was the initial speed of the ball?

  1. A) 21.5 m/s
  2. B) 19.7 m/s
  3. C) 2.2 m/s
  4. D) 39 m/s

Answer:  A

Var: 50+

 

21) A child is sitting on the outer edge of a merry-go-round that is 18 m in diameter. If the merry-go-round makes 8.3 rev/min, what is the velocity of the child in m/s?

  1. A) 7.8 m/s
  2. B) 15.6 m/s
  3. C) 1.2 m/s
  4. D) 5.5 m/s

Answer:  A

Var: 50+

22) Two particles, A and B, are in uniform circular motion about a common center. The acceleration of particle A is 4.7 times that of particle B. Particle B takes 2.4 times as long for a rotation as particle A. The ratio of the radius of the motion of particle A to that of particle B is closest to:

  1. A) 0.82
  2. B) 2.0
  3. C) 3.8
  4. D) 0.51
  5. E) 11

Answer:  A

Var: 50+

 

23) An aircraft performs a maneuver called an aileron roll. During this maneuver, the plane turns like a screw as it maintains a straight flight path, by using its ailerons to set the wings in circular motion. If it takes the plane 35 s to complete the circle and each wing length is 4.6 m, what is the acceleration of the wing tip?

  1. A) 0.15 m/s2
  2. B) 0.69 m/s2
  3. C) 6.7 m/s2
  4. D) 1.4 m/s2

Answer:  A

Var: 50+

 

24) A small boat is moving at a velocity of 3.35 m/s when it is accelerated by a river current perpendicular to the initial direction of motion. If the current acceleration is 0.750 m/s2, what will the new velocity of the boat be after 33.5 s?

  1. A) 25.3 m/s at 82.4° from initial direction of motion
  2. B) 25.3 m/s at 7.59° from initial direction of motion
  3. C) 640.1 m/s at 82.4° from initial direction of motion
  4. D) 640.1 m/s at 7.59° from initial direction of motion

Answer:  A

Var: 50+

25) A ship moving initially at 10.7 m/s due North, drifts due NE at the same speed. To correct the bearing, the captain accelerates the engine and turns the rudder NW. If the engines deliver a constant acceleration of 4.4 m/s2, how long will it take to assume the original course again?

  1. A) 2.4 s
  2. B) 3.4 s
  3. C) 1.7 s
  4. D) 1.2 s

Answer:  A

Var: 50+

 

26) A plane flying at 70.0 m/s suddenly stalls. If the acceleration during the stall is 9.8 m/s2 directly downward, the stall lasts 5.0 s, and the plane was originally climbing at 25° to the horizontal, what is the velocity after the stall?

  1. A) 66 m/s at -17°
  2. B) 66 m/s at +17°
  3. C) 80 m/s at -37°
  4. D) 80 m/s at +37°

Answer:  A

Var: 1

 

 

27) An electron moves with a horizontal velocity of 3.0 × 106 m/s as it enters a deflector inside a TV tube. The electron strikes the screen after traveling 17.0 cm horizontally and 40.0 cm vertically upward. What is the constant vertical acceleration provided by the deflector?

  1. A) 2.5 × 1014m/s2
  2. B) 8.3 × 102m/s2
  3. C) 1.4 × 104m/s2
  4. D) 1.2 × 1014m/s2

Answer:  A

Var: 50+

 

28) A boat crosses a river at a constant engine speed of 8.0 cm/s under the influence of a constant perpendicular current acceleration of 0.060 m/s2. How far off a straight course does it drift in 2.3 min?

  1. A) 570 m
  2. B) 0.16 m
  3. C) 4.1 m
  4. D) 1700 m

Answer:  A

Var: 50+

29) A glider is tugged by an airplane at 81 m/s when it is released. If the original speed was along the horizontal and the glider is now under a constant acceleration of 2.4 m/s2 at 1.1° below the horizontal due to air drag, how long will it take to reach the ground 5.7 km below?

  1. A) 500 s
  2. B) 250,000 s
  3. C) 2.2 s
  4. D) 4.8 s

Answer:  A

Var: 50+

 

30) What is the maximum distance we can shoot a dart, provided our toy dart gun gives a maximum initial velocity of 2.78 m/s?

  1. A) 0.79 m
  2. B) 1.58 m
  3. C) 1.39 m
  4. D) More information needed

Answer:  A

Var: 50+

 

 

31) A fisherman casts his bait into the river at an angle of 25°. As the line unravels, he notices that the bait and hook reach a maximum height of 3.9 m. What was the initial velocity he launched the bait with?

  1. A) 21 m/s
  2. B) 9.2 m/s
  3. C) 10 m/s
  4. D) 8.4 m/s

Answer:  A

Var: 30

 

32) A hobby rocket reaches a height of 72.3 m and lands 111 m from the launch point. What was the angle of launch?

  1. A) 69.0°
  2. B) 67.4°
  3. C) 22.6°
  4. D) -44.8°

Answer:  A

Var: 50+

33) A plane flies directly from city A to city B, which are separated by 2300 mi. From A to B, the plane flies into a 65 mi/h headwind. On the return trip from B to A, the wind velocity is unchanged. The trip from B to A takes 65 min less than the trip from A to B. What is the airspeed (assumed constant) of the plane?

  1. A) 530 mi/h
  2. B) 400 mi/h
  3. C) 480 mi/h
  4. D) 610 mi/h

Answer:  A

Var: 31

 

34) You are taking a turn at 23.0 m/s on a ramp of radius 39.0 m. What is your acceleration?

  1. A) 13.6 m/s2
  2. B) 0.590 m/s2
  3. C) 66.1 m/s2
  4. D) 1.70 m/s2

Answer:  A

Var: 50+

 

 

35) An aircraft performs a maneuver called an aileron roll. During this maneuver, the plane turns like a screw as it maintains a straight flight path, by using its ailerons to set the wings in circular motion. Due to structural strength, an airplane can only withstand an acceleration of 6.1 m/s2 on its wing tips. If the wing span is 6.0 m, what is the shortest time it can make a full turn when it performs an aileron roll?

  1. A) 4.4 s
  2. B) 6.0 s
  3. C) 0.70 s
  4. D) 6.2 s

Answer:  A

Var: 50+

 

3.2   True/False

 

1) The product of a vector by a scalar is a vector having the same direction of the original vector but a different magnitude.

Answer:  FALSE

Var: 1

 

2) The magnitude of a vector cannot be smaller than the magnitude of any of its components.

Answer:  TRUE

Var: 1

3) The magnitude of the resultant of two vectors must be greater than or equal to the magnitude of each of these vectors.

Answer:  FALSE

Var: 1

 

4) The magnitude of the displacement vector from A to B can never be less than the distance from A to B, but it can be greater than that distance.

Answer:  FALSE

Var: 1

 

5) The magnitude of the displacement vector of an object is equal to the distance that object has moved.

Answer:  FALSE

Var: 1

 

6) The components of a vector will be the same no matter what coordinate system is used to express that vector.

Answer:  FALSE

Var: 1

 

7) A grasshopper leaps into the air at a 62 degree angle above the horizontal. At its highest point, the grasshopper’s velocity and acceleration are equal to zero.

Answer:  FALSE

Var: 1

 

8) You throw a 5.0 kg stone from the top of a cliff with an initial vertical velocity of 8.0 m/s downward and an initial horizontal velocity of 7.0 m/s away from the cliff, and it feels no air resistance. After the stone is in the air but free of your hand, its acceleration remains constant at 9.8 m/s2 downward but its speed changes.

Answer:  TRUE

Var: 1

 

9) You can launch a projectile with a fixed initial speed but at any angle above the horizontal, and it feels no air resistance. The time for it to return to the ground does not depend on the angle at which you launch it.

Answer:  FALSE

Var: 1

 

10) A ball is thrown at an angle above the horizontal from the top of a cliff and feels no air resistance. A runner at the base of the cliff moves horizontally so that she is always under the ball. In this runner’s reference frame, the path of the ball is a straight line rather than a parabola.

Answer:  TRUE

Var: 1

11) A football is kicked toward the goal posts and feels no air resistance. While it is in the air, the only force acting on it is 9.8 m/s2 downward due to gravity.

Answer:  FALSE

Var: 1

 

3.3   Conceptual

 

1) The sum of the two vectors  and  is equal to zero. What can you conclude about  and ?

Answer:  The vectors  and  have the same magnitude but are in opposite directions.

Var: 1

 

2) What is the minimum number of vectors (none of which have the same magnitude) for which it is theoretically possible that the sum of those vectors can be equal to zero?

Answer:  It is possible with three (or more) vectors. Three is the minimum number for which the condition may be satisfied.

Var: 1

 

3) Which of the following is NOT a vector?

  1. A) speed
  2. B) acceleration
  3. C) velocity
  4. D) displacement

Answer:  A

Var: 1

 

4) Shown here are the velocity and acceleration vectors for an object in several different types of motion. In which case is the object slowing down and turning to its right?

  1. A)
  2. B)
  3. C)
  4. D)
  5. E)

Answer:  B

Var: 1

5) Shown here are the velocity and acceleration vectors for an object in several different types of motion. In which case is the object’s velocity changing while its speed is not changing?

  1. A)
  2. B)
  3. C)
  4. D)
  5. E) None of these cases

Answer:  D

Var: 1

 

6) Which of the following ideas is true about projectile motion with no air drag?

  1. A) + = constant.
  2. B) The acceleration is +g when the object is rising and -g when falling.
  3. C) The velocity of the object is zero at the point of maximum elevation.
  4. D) The trajectory will depend on the object’s mass as well as its initial velocity and launch angle.
  5. E) The horizontal motion is independent of the vertical motion.

Answer:  E

Var: 1

7) Two bullets are fired simultaneously parallel to a horizontal plane. The bullets have different masses and different initial velocities. Which one will strike the plane first?

  1. A) the fastest one
  2. B) the slowest one
  3. C) the heaviest one
  4. D) the lightest one
  5. E) They strike the plane at the same time.

Answer:  E

Var: 1

 

8) Are projectiles subject to constant acceleration in two dimensions?

Answer:  Yes, they are subject to the constant acceleration (g) along the vertical.

Var: 1

 

9) To achieve maximum range of a projectile, for a fixed initial velocity, on Earth we must launch it at 45°. If we were at the moon should we do the same?

Answer:  Yes, only g will be different at the moon. Note that in this case the presence of the atmosphere is neglected.

Var: 1

 

10) If I throw a rock in a lake at 30° or 60° from horizontal, with the same initial speed, it will splash on the same spot. So what is the difference? Should we only consider angles from 0° to 45°?

Answer:  The difference is that the one launched at 30° will travel a shorter arc, and thus it will splash in a shorter time span than the other. Consequently, the 60° launched rock will reach a higher elevation. You trade time of flight for altitude.

Var: 1

 

11) Bob and Biff throw identical rocks off a tall building at the same time.  Bob throws his rock straight downward. Biff throws his rock  downward and outward such that the angle between the initial velocity of the rock and the horizon is 30 degrees. Biff throws the rock with a speed twice that of Bob’s rock. Which rock hits the ground first (assume the ground near the building is flat)?

  1. A) They hit at the same time.
  2. B) Bob’s rock
  3. C) Biff’s rock
  4. D) Impossible to determine

Answer:  A

Var: 1

 

College Physics, 2e (Knight)

Chapter 13   Fluids

 

13.1   Quantitative

 

1) A standard atmosphere has a pressure versus altitude relation approximated by

 

            ρ = Poe-αh,

 

with α = 0.116 km-1. An aircraft flies at 30,000 ft but maintains a cabin pressure of that at

8000 ft. What force is exerted by air pressure on a square meter of cabin wall area?

  1. A) 4.1 × 104N
  2. B) 124 N
  3. C) 3.5 × 104N
  4. D) 7.6 × 104N

Answer:  A

Var: 1

 

 

 

2) A container has a vertical tube, whose inner radius is  24.00 mm, connected to it at its side. An unknown liquid reaches level A in the container and level B in the tube—level A being

5.0 cm higher than level B. The liquid supports a 20.0 cm high column of oil, between levels B and C, whose density is 570 kg/m3. In the figure, the mass of the oil, in grams, is closest to:

  1. A) 210
  2. B) 410
  3. C) 620
  4. D) 820
  5. E) 1000

Answer:  A

Var: 50+

 

3) A container has a vertical tube, whose inner radius is 12.00 mm, connected to it at its side. An unknown liquid reaches level A in the container and level B in the tube—level A being 5.0 cm  higher than level B. The liquid supports a 20.0 cm high column of oil, between levels B and C, whose density is 320 kg/m3. In the figure, the gauge pressure at level B is closest to:

  1. A) 630 Pa
  2. B) 310 Pa
  3. C) 470 Pa
  4. D) 790 Pa
  5. E) 940 Pa

Answer:  A

Var: 50+

 

4) A football coach in hopes of improving his kicker’s performance fills a 0.9 kg football with helium rather than air. Assuming that the football contains a volume of helium equal to the air it replaces at standard temperature and pressure, what change in relative weight of the football (change in weight divided by weight) is to be expected? The volume of the football is 1.6 l.

  1. A) 1.81 × 10-3
  2. B) 1.42 × 10-3
  3. C) 1.96 × 10-4
  4. D) 1.01 × 10-3

Answer:  A

Var: 1

 

5) A pump uses a piston of 15 cm diameter which moves 2 cm/s. What is the fluid velocity of a tube 3 mm in diameter?

  1. A) 50 m/s
  2. B) 50 cm/s
  3. C) 6 cm/s
  4. D) 22 cm/s

Answer:  A

Var: 1

 

6) An aspirator operates as a pump. Water flows by a small tube perpendicular to the flow of the water. If the water flows at 3.7 m/s, what pressure differential is present if the other end of the tube is maintained at atmospheric pressure?

  1. A) 0.93 atm
  2. B) 0.69 atm
  3. C) 0.31 atm
  4. D) -0.31 atm

Answer:  A

Var: 1

 

7) A submarine in neutral buoyancy is 100 m below the surface of the water. What air pressure must be supplied to remove water from the ballast tanks in order for the submarine to surface?

  1. A) 9.9 × 105N/m2
  2. B) 9.8 × 105N/m2
  3. C) 4.9 × 105N/m2
  4. D) The cross-sectional area of the tank is needed.

Answer:  A

Var: 1

 

8) A hollow steel ball of diameter 3 m barely floats in water. What is the wall thickness of the ball? (ρFe = 7.87 g/cm3)

  1. A) 6.6 cm
  2. B) 37 cm
  3. C) 131 cm
  4. D) 79 cm

Answer:  A

Var: 1

 

9) Water is pumped out of a well at 5.000 m/s through a 8.000 cm diameter hose. The well is 30.00 ft deep. What power is needed by the pump?

  1. A) 2253 W
  2. B) 230 W
  3. C) 6894 W
  4. D) The area of the well is needed.

Answer:  A

Var: 45

 

10) A compressed gas with a total mass of 203 kg is stored in a spherical container that has a radius of 0.521 m. What is the density of the compressed gas?

  1. A) 343 kg/m3
  2. B) 209 kg/m3
  3. C) 254 kg/m3
  4. D) 305 kg/m3

Answer:  A

Var: 50+

11) One of the dangers of tornados and hurricanes is the rapid drop in air pressure that is associated with such storms. Assume that the air pressure inside of a sealed house is 1.02 atm when a hurricane hits. The hurricane rapidly decreases the external air pressure to 0.910 atm. What net force (directed outwards) is exerted on a 2.02 m square window on the house?

  1. A) 4.55 × 104N
  2. B) 5.14 × 104N
  3. C) 4.78 × 105N
  4. D) 5.37 × 105N

Answer:  A

Var: 50+

 

12) A water tank is filled to a depth of 10 m and the tank is 20 m above ground. The water pressure at ground level in a hose 2 cm in diameter is closest to:

  1. A) 3.9 × 105N/m2
  2. B) 2.0 × 104N/m2
  3. C) 9.2 N/m2
  4. D) The cross-sectional area of the tank is needed.

Answer:  A

Var: 1

 

13) The density of material at the center of a neutron star is approximately 1.00 × 1018 kg/m3.  Calculate the mass of a cube of this material that is 1.76 microns on each side. One micron is equal to 1 × 10-6 m.

  1. A) 5.45 kg
  2. B) 4.74 kg
  3. C) 6.16 kg
  4. D) 6.70 kg

Answer:  A

Var: 50+

 

14) Calculate the pressure exerted on the ground by a 79 kgperson standing on one foot. Assume that the bottom of the person’s foot is 13 cm wide and 28 cm long.

  1. A) 2.1 × 104Pa
  2. B) 2.2 × 103Pa
  3. C) 4.8 × 104Pa
  4. D) 5.3 × 104Pa

Answer:  A

Var: 36

15) A cap 7.000 cm in diameter plugs an opening in a spherical container 1.000 m in diameter at atmospheric pressure. The container is submerged to a depth of 10.00 ft in water. What force is needed to remove the plug? Assume the plug is planar and the pressure over the container is equalized.

  1. A) 115 N
  2. B) 460 N
  3. C) 4.608 × 106 N
  4. D) 378 N

Answer:  A

Var: 50+

 

 

16) A tank of water at rest is 2.0000 m deep. It is then accelerated at 5.0000 m/s2 parallel to the original water surface, so that the front edge of the water in the tank is lowered to 1/2 its original value. What is the water pressure in the tank at the bottom back edge?

  1. A) 29,430.0013 N/m2
  2. B) 9 N/m2
  3. C) 9810.00042 N/m2
  4. D) The length of the tank is needed.

Answer:  A

Var: 24

 

17) A house is supported equally on 18 pilings each with a 0.5 m2 area at the base. The soil can withstand 5 psi. What could be the maximum mass of the house?

  1. A) 3.2 × 104kg
  2. B) 6.3 × 104kg
  3. C) 8.0 × 104kg
  4. D) 1.6 × 104kg

Answer:  A

Var: 50+

 

18) How many logs 3.00 m long and 18.0 cm in diameter are needed to just barely float a

2500.0 kg car? (ρwood = 0.720 g/cm3)

  1. A) 118
  2. B) 117
  3. C) 30
  4. D) 29

Answer:  A

Var: 50+

19) A 4.7 kg solid sphere, made of metal whose density is 4000 kg/m3, is suspended by a cord. The density of water is 1000 kg/m3. When the sphere is immersed in water, the tension in the cord is closest to:

  1. A) 35 N
  2. B) 40 N
  3. C) 46 N
  4. D) 52 N
  5. E) 58 N

Answer:  A

Var: 50+

 

 

20) The body takes a mass of air into the lungs directly proportional to the ambient pressure. A diver who uses 27 psi/min at sea level has an air tank initially containing 1800 psi.  How long can the diver work at a water depth of 40.0 ft.?

  1. A) 31 min
  2. B) 56 min
  3. C) 107 min
  4. D) 2 min

Answer:  A

Var: 50+

 

21) How much would a lead brick 2.0 in × 2.0 in × 8.0 in weigh if placed in oil with density

ρ = 0.92 g/cm3? (ρPb = 11.4 g/cm3)

  1. A) 5.5 kg
  2. B) 0.34 kg
  3. C) 6 kg
  4. D) 0.48 kg

Answer:  A

Var: 20

 

22) A 200.0 kg flat-bottomed boat floats in fresh water, which has a density of 1000.0 kg/m3. Assuming that the base of the boat is 1.42 m wide and 4.53 m long, how much of the boat is submerged when it carries three passengers whose total mass is 193 kg?

  1. A) 6.11 cm
  2. B) 6.48 cm
  3. C) 6.84 cm
  4. D) 7.33 cm

Answer:  A

Var: 50+

23) A  8.6 kg solid sphere, made of metal whose density is 3400 kg/m3, is suspended by a cord. When the sphere is immersed in a liquid of unknown density, the tension in the cord is  38 N. The density of the liquid is closest to:

  1. A) 1900 kg/m3
  2. B) 1700 kg/m3
  3. C) 1600 kg/m3
  4. D) 1500 kg/m3
  5. E) 1400 kg/m3

Answer:  A

Var: 50+

 

 

24) A 9.8 kg solid sphere, made of metal whose density is  3000 kg/m3, is suspended by a cord. The sphere floats when placed in a liquid of density 4200 kg m3. The fraction of the volume of the sphere that is submerged is closest to:

  1. A) 0.71
  2. B) 0.73
  3. C) 0.75
  4. D) 0.69
  5. E) 0.67

Answer:  A

Var: 50+

 

25) How many grams of ethanol (specific gravity 0.80) should be added to 5 grams of chloroform (specific gravity 1.50) if the resulting mixture is to have a specific gravity of 1.20?

  1. A) 2.0 g
  2. B) 2.4 g
  3. C) 1.8 g
  4. D) 4.4 g
  5. E) 1.6 g

Answer:  A

Var: 1

 

26) Consider a very small hole in the bottom of a tank 20.0 cm in diameter filled with water to a height of 50.0 cm.  Find the speed at which the water exits the tank through the hole.

  1. A) 3.13 m/s
  2. B) 9.80 m/s
  3. C) 31.8 m/s
  4. D) 34.9 m/s

Answer:  A

Var: 50+

27) A venturi is constructed of a 9.0 cm diameter pipe with a 2.0 cm diameter throat. Water pressure in the pipe is twice atmospheric pressure and it flows with a velocity of 0.30 m/s.

What is the pressure in the throat?

  1. A) 1.8 atm
  2. B) 0.18 atm
  3. C) 2.2 atm
  4. D) 2.0 atm

Answer:  A

Var: 16

 

 

28) Water flowing through a pipe suddenly comes to a section of pipe where the pipe diameter decreases to 86% of its previous value. If the speed of the water in the larger section of the pipe was 32 m/s, what is its speed in this smaller section?

  1. A) 43 m/s
  2. B) 37 m/s
  3. C) 28 m/s
  4. D) 24 m/s

Answer:  A

Var: 50+

 

29) The Tonga Trench in the Pacific Ocean is 36,000 feet deep. Assuming that sea water has an average density of 1.04 g/cm3, calculate the absolute pressure at the bottom of the trench in atmospheres.

  1. A) 1.1 × 103atm
  2. B) 1.1 × 108atm
  3. C) 1.1 × 105atm
  4. D) 1.1 × 106atm
  5. E) 2.1 atm

Answer:  A

Var: 1

 

30) A rectangular wooden block measures 10.0 cm × 4.00 cm × 2.00 cm. When the block is placed in water, it floats horizontally, with its bottom face 1.65 cm below the surface. What is the density of the wood?

  1. A) 0.825 g/cm3
  2. B) 1.21 g/cm3
  3. C) 1.65 g/cm3
  4. D) 0.606 g/cm3
  5. E) 0.350 g/cm3

Answer:  A

Var: 1

 

 

 

31) A pressurized cylindrical tank, 5.0 m in diameter, contains water that emerges from the pipe at point C, with a velocity of 13 m/s. Point A is 10 m above point B and point C is 3 m above point B. The area of the pipe at point B is 0.08 m2 and the pipe narrows to an area of 0.04 m2 at point C. Assume the water is an ideal fluid in laminar flow. The density of water is 1000 kg/m3.  In the figure, the mass flow rate in the pipe is closest to:

  1. A) 520 Kg/s
  2. B) 470 Kg/s
  3. C) 420 Kg/s
  4. D) 360 Kg/s
  5. E) 310 Kg/s

Answer:  A

Var: 50+

 

13.2   True/False

 

1) If the hydrostatic pressure at a certain depth in the ocean is 2 atm, the hydrostatic pressure will be 4 atm if you go twice as deep.

Answer:  FALSE

Var: 1

 

2) A long vertical metal cylinder is filled with oil.  If a piston pushes on the top of this cylinder and increases the pressure there by 6,000 Pa, the pressure at the bottom will increase considerably more due to the weight of the oil.

Answer:  FALSE

Var: 1

 

3) According to Pascal’s principle, if you increase the pressure enough so that the force at one end of an oil-filled tube increases by 10 N, the force will increase at all points in the tube by 10 N.

Answer:  FALSE

Var: 1

4) When an object is floating, the buoyant force on it is just equal to its weight.

Answer:  TRUE

Var: 1

 

 

5) If you increase the pressure on the surface of a can of water, you will increase the buoyant force on objects placed in that water.

Answer:  FALSE

Var: 1

 

6) If the gauge pressure at a certain depth in Lake Michigan is 3.5 atmospheres, the absolute pressure at that depth is 4.5 atm.

Answer:  TRUE

Var: 1

 

7) If a uniform sphere is compressed to half of its original diameter, its mass remains the same but its density becomes 8 times as great.

Answer:  TRUE

Var: 1

 

8) Water flows through a pipe having a varying width.  More water flows per second through the wide section than through the narrow section because there is more room for it to flow.

Answer:  FALSE

Var: 1

 

13.3   Conceptual

 

1) An air bubble underwater has the same pressure as that of the water. As the air bubble rises toward the surface (and its temperature remains constant), the volume of the air bubble

  1. A) increases.
  2. B) decreases.
  3. C) remains constant.
  4. D) increases or decreases, depending on the rate it rises.

Answer:  A

Var: 1

2) The tires of a car support the weight of a stationary car. If one tire has a slow leak, the air pressure within the tire will _______ with time, the surface area between the tire and the road will ________ with time, and the net force the tire exerts on the road will ___________ with time.

  1. A) decrease, increase, remain constant
  2. B) decrease, increase, decrease
  3. C) decrease, decrease, decrease
  4. D) increase, increase, increase
  5. E) decrease, increase, increase

Answer:  A

Var: 1

 

 

3) A tire of an automobile has a gauge pressure of 30 psi at the top of a mountain, and the air temperature inside the tire is 300 K. The atmospheric pressure at the top of the mountain is  0.7 atm. The car is driven down to sea level, where the atmospheric pressure is 1.0 atm, and the air inside the tire is heated to 350 K. At sea level, assuming no leaks, the gauge pressure of the tire will be

  1. A) lower.
  2. B) higher.
  3. C) the same.

Answer:  A

Var: 1

 

4) In England in the Middle Ages an extensive system of canals was used for transportation. Some of these canals crossed over canyons by flowing over bridges (viaducts). Suppose that a heavily loaded barge crossed over such a waterway bridge.

  1. A) The force downward on the bridge would increase because of the added weight of the barge.
  2. B) The force on the bridge would not change when the barge passed over.
  3. C) The force on the barge would become less because some water would be squeezed off of the bridge.
  4. D) The force on the bridge would become less because of the buoyancy effect of the water on the barge.
  5. E) Whether or not the force on the bridge would increase or decrease would depend on whether the water was flowing or stationary.

Answer:  B

Var: 1

5) A barge loaded with lumber and iron ore floats in a lock by a dam (a closed pool of water like a big swimming pool). If some of the cargo is thrown overboard, the level of water in the lock will

  1. A) rise.
  2. B) drop.
  3. C) stay the same.
  4. D) rise, provided it is lumber that is thrown overboard.
  5. E) rise, provided it is iron ore that is thrown overboard.

Answer:  C

Var: 1

 

6) A waitress fills your water glass with ice water (containing many ice cubes) such that the liquid water is perfectly level  with the rim of the glass. As the ice melts,

  1. A) the liquid-water level remains flush with the rim of the glass.
  2. B) the liquid-water level rises, causing water to run down the outside of the glass.
  3. C) the liquid-water level decreases.

Answer:  A

Var: 1

 

 

7) A spherical ball of lead (density 11.3 g/cm3) is placed in a tub of mercury (density 13.6 g/cm3). Which answer best describes the result?

  1. A) The lead ball will float with about 83% of its volume above the surface of the mercury.
  2. B) The lead ball will float with its top exactly even with the surface of the mercury.
  3. C) The lead ball will float with about 17% of its volume above the surface of the mercury.
  4. D) The lead will sink to the bottom of the mercury.
  5. E) None of the above

Answer:  C

Var: 1

 

 

8) In the figure, fluid fills the container shown here. At which of the indicated points is the pressure greatest?

  1. A) A
  2. B) B
  3. C) C
  4. D) D
  5. E) The pressure is the same at each of the labeled points.

Answer:  E

Var: 1

 

9) A wooden block contains some nails so that its density is exactly equal to that of water. If it is placed in a tank of water and released from rest when it is completely submerged, it will

  1. A) rise to the surface.
  2. B) sink to the bottom.
  3. C) remain where it is released.

Answer:  C

Var: 1

 

 

10) The Bernoulli effect is described by the equation

P1 + 1/2ρ v21 + ρg h1 = P2 + 1/2ρ v22 + ρgh2

 

The origin of this relation is that it is a statement of

  1. A) the conservation of linear momentum.
  2. B) Newton’s Third Law, i.e., equal action and reaction.
  3. C) the conservation of energy for a moving fluid.
  4. D) the continuity principle for fluids.
  5. E) F = ma as applied to a fluid.

Answer:  C

Var: 1

11) The Bernoulli effect is responsible for the lift force on an airplane wing. Wings must therefore be designed so as to insure that

  1. A) air molecules will be deflected downward when they hit the wing.
  2. B) air molecules will be deflected upward when they hit the wing.
  3. C) air molecules move more rapidly past the upper surface of the wing than past the lower surface.
  4. D) air molecules move more rapidly past the lower surface of the wing than past the upper surface.
  5. E) wings are thick enough to create a significant pressure difference between the top and bottom surfaces of the wings because of the different heights of these surfaces.

Answer:  C

Var: 1

 

12) Consider a brick that is totally immersed in water. The long edge of the brick is vertical. The pressure on the brick is

  1. A) the same on all surfaces of the brick.
  2. B) greatest on the face with largest area.
  3. C) greatest on the top of the brick.
  4. D) greatest on the sides of the brick.
  5. E) greatest on the bottom of the brick.

Answer:  E

Var: 1

College Physics, 2e (Knight)

Chapter 23   Circuits

 

23.1   Quantitative

 

1) Each of the resistors in the circuit shown have a resistance of 160.0 Ω. What is the equivalent resistance of the circuit?

  1. A) 400.0 Ω
  2. B) 640.0 Ω
  3. C) 480.0 Ω
  4. D) 160.0 Ω

Answer:  A

Var: 41

 

2) The resistors in the circuit shown each have a resistance of 600 Ω. What is the equivalent resistance of the circuit?

  1. A) 600 Ω
  2. B) 2400 Ω
  3. C) 150 Ω
  4. D) 1200 Ω

Answer:  A

Var: 9

 

3) Refer to the figure shown. What is the current through the 4.0 Ω  resistor?

 

  1. A) 1.5 A
  2. B) 4.0 A
  3. C) 0.43 A
  4. D) 1.1 A

Answer:  A

Var: 50+

 

4) A 10.0 V battery is connected across two resistors in series. If the resistors have resistances of 840.0 Ω and 590.0 Ω , what is the voltage drop across the 590.0 Ω resistor?

  1. A) 4.1 V
  2. B) 5.9 V
  3. C) 14 V
  4. D) 7.0 V

Answer:  A

Var: 50+

 

5) In the circuit shown, what current does the ammeter read?

 

  1. A) 0.10 A
  2. B) 0.078 A
  3. C) 0.21 A
  4. D) 0.14 A

Answer:  A

Var: 50+

 

6) What is the current through resistor R1 in the circuit shown?

 

  1. A) 0.30 A
  2. B) 0.20 A
  3. C) 0.00 A
  4. D) 5.72 A

Answer:  A

Var: 50+

 

7) What is the current through resistor R1 in this circuit?

 

  1. A) 0.040 A
  2. B) 0.10 A
  3. C) 0.022 A
  4. D) 0.0089 A

Answer:  A

Var: 50+

 

8) What is the current through resistor R3 in this circuit?

 

  1. A) 0.0063 A
  2. B) 1.5 A
  3. C) 0.0045 A
  4. D) 0.013 A

Answer:  A

Var: 50+

 

 

9)

A multiloop circuit is given. It is not necessary to solve the entire circuit. In the figure shown, the current I1 is closest to:

  1. A) -3 A
  2. B) 3 A
  3. C) 10 A
  4. D) -10 A
  5. E) zero

Answer:  A

Var: 50+

 

10)

A multiloop circuit is given. It is not necessary to solve the entire circuit. In the figure shown, the current I2 is closest to:

  1. A) -2 A
  2. B) 2 A
  3. C) 8 A
  4. D) -8 A
  5. E) zero

Answer:  A

Var: 50+

 

11)

A multiloop circuit is given. It is not necessary to solve the entire circuit. In the figure shown, the emf ε1 is closest to:

  1. A) -28 V
  2. B) 28 V
  3. C) 68 V
  4. D) 72 V
  5. E) -72 V

Answer:  A

Var: 50+

 

12)

A multiloop circuit is given. It is not necessary to solve the entire circuit. In the figure shown, the potential difference Vag is closest to:

  1. A) -12 V
  2. B) 28 V
  3. C) -28 V
  4. D) -60 V
  5. E) 60 V

Answer:  A

Var: 50+

 

 

 

13) In the figure shown, what is the power dissipated in the 2 ohm resistance in the circuit?

  1. A) 5.33 W
  2. B) 8.0 W
  3. C) 6.67 W
  4. D) 2.67 W
  5. E) 3.56 W

Answer:  E

Var: 1

 

14)

 

Initially, for the circuit shown, the switch S is open and the capacitor is uncharged.The switch S is closed at time t = 0. In the figure shown, when the time t is equal to 8.0 s, the charge on the capacitor, in μC, is closest to:

  1. A) 2300
  2. B) 1800
  3. C) 2700
  4. D) 3200
  5. E) 3600

Answer:  A

Var: 50+

 

15)

 

Initially, for the circuit shown, the switch S is open and the capacitor is uncharged.The switch S is closed at time t = 0.  In  the figure shown, when the time t is equal to 20.0 s, the potential difference across the resistor is closest to:

  1. A) 8.6 V
  2. B) 10 V
  3. C) 12 V
  4. D) 14 V
  5. E) 15 V

Answer:  A

Var: 50+

 

16) The capacitor shown in the circuit in the figure is initially uncharged when the switch S is suddenly closed. After one time constant, the current through the resistor will be closest to:

 

 

  1. A) 0.00 A
  2. B) 0.74 A
  3. C) 1.0 A
  4. D) 1.3 A
  5. E) 2.0 A

Answer:  B

Var: 1

 

17) A  4.0 μF capacitor is connected in series to a resistor. If an emf source is connected in series to this arrangement, and if the voltage drop across the capacitor is one-half the applied emf

.0 ms after the emf source has been connected, what is the resistance of the circuit?

  1. A) 2.9 kΩ
  2. B) 1.4 kΩ
  3. C) 0.35 kΩ
  4. D) 0.72 kΩ

Answer:  A

Var: 41

 

18)  A  1.0 μF capacitor is charged until it acquires a potential difference of 700.0 V across its plates, then the emf source is removed. If the capacitor is then discharged through a 200.0 kΩ resistance of a circuit, what is the voltage drop across the capacitor 7.0 ms later?

  1. A) 680 V
  2. B) 720 V
  3. C) 24 V
  4. D) -25 V

Answer:  A

Var: 50+

 

19)

Initially, for the circuit shown, the switch S is open and the capacitor voltage is 80 V. The switch S is closed at time t = 0. In the figure shown, the capacitor voltage when the time t is equal to 40.0 s is closest to:

  1. A) 53 V
  2. B) 60 V
  3. C) 66 V
  4. D) 73 V
  5. E) 80 V

Answer:  A

Var: 50+

 

23.2   True/False

 

1) Ohm’s law is a fundamental law of physics and is therefore obeyed by all materials.

Answer:  FALSE

Var: 1

 

2) If the graph of the current through a resistor as a function of the potential difference across it is a straight line with a positive slope passing through the origin, the resistor obeys Ohm’s law and the slope of this graph is equal to the resistance of this resistor.

Answer:  FALSE

Var: 1

 

3) The high potential end of a resistor is the end at which the current enters it.

Answer:  TRUE

Var: 1

 

4) If a 75 W bulb and a 100 W bulb are connected in series across a 120 V outlet, the 75 W bulb will dissipate 75 W of power and the 100 W bulb will dissipate 100 W of power.

Answer:  FALSE

Var: 1

5) When a potential difference of 10 V is placed across a certain solid cylindrical resistor, the current through it is 2.0 A.  If the diameter of this resistor is now tripled, the current will be 18 A.

Answer:  TRUE

Var: 1

 

6) The potential across the terminals of a store-bought 1.5 V AAA battery always remains at 1.5 V unless the battery has gone dead.

Answer:  FALSE

Var: 1

 

7) In a discharging RC circuit, it takes one time constant for the capacitor to discharge completely.

Answer:  FALSE

Var: 1

 

23.3   Conceptual

 

1) Of voltmeters and ammeters, which is/are connected in series?

Answer:  Ammeters

Var: 1

 

2) Why is it appropriate that electromotive force be measured in volts?

Answer:  Electromotive force is work per unit charge done by a source.

Var: 1

 

3) A circuit has a branch in it. If the current in each of the two paths that leave the branch is  how much current does the wire coming into the branch carry?

Answer:  6 mA

Var: 1

 

4) Which will drain a battery faster, a circuit with a resistance of 10 kΩ or a circuit with a resistance of 1Ω?

Answer:  A circuit with a resistance of 1Ω

Var: 1

 

5) A circuit requires a 500 Ω resistor, but all that is available are 1 kΩ resistors. If the 1 kΩ resistors are in abundant supply, how can they be combined to achieve the desired resistance?

Answer:  Two 1 kΩ resistors can be connected in parallel.

Var: 1

 

6) Draw a circuit with two batteries, a resistor between them, and a capacitor in parallel with the resistor. The batteries are connected negative pole to positive pole.

  1. A)

 

  1. B)

 

C)

 

  1. D)

 

Answer:  A

Var: 1

 

7) How are the two batteries in the figure connected? State whether they are in parallel or in series and give the polarity of each battery at its connection to the other.

  1. A) in series, positive to positive
  2. B) in series, negative to negative
  3. C) in parallel, positive to positive
  4. D) in series, positive to negative

Answer:  A

Var: 1

 

8) Draw a circuit consisting of a battery connected to two resistors, R1 and R2, in series with each other and a capacitor C connected across the resistors.

  1. A)
  2. B)
  3. C)

 

  1. D)

Answer:  A

Var: 1

 

 

9) Draw a circuit with a battery connected to four resistors, R1, R2, R3, and R4. Resistors R1 and R2 are connected in parallel, resistors R3 and R4 are connected in parallel, and both parallel pairs of resistors are connected in series.

 

  1. A)

 

  1. B)

 

  1. C)

 

  1. D)

 

 

Answer:  A

Var: 1

 

 

10) A resistor is made out of a low wire having a length L. Each end of the wire is attached to a terminal of a battery having a constant  voltage Vo. A current I flows through the wire. If the wire were cut in half, making two wires of length L/2, and both wires were attached to the battery (the end of both wires attached to one terminal, and the other ends attached to the other terminal), what would be the total current flowing through the two wires?

  1. A) 4I
  2. B) 2I
  3. C) I
  4. D) I/2

Answer:  A

Var: 1

11) A 9 V battery is hooked up to two resistors in series. One has a resistance of 5 Ω and the other has a resistance of 10 Ω. Several locations along the circuit are marked with letters, as shown in the figure. Which statement is true?

 

  1. A) The current at A is equal to the current at B, which is equal to the current at C, which is equal to the current at D.
  2. B) The current at A is greater than the current at B, which is equal to the current at C, which is greater than the current at D.
  3. C) The current at A is greater than the current at B, which is greater than the current at C, which is greater than the current at D.

Answer:  A

Var: 1

 

12) Identical lightbulbs are attached to identical batteries, as shown in the figure. The ranking (from lowest to highest) of the total power emitted from the lightbulb(s) is:

 

  1. A) y, z, x
  2. B) x, y, z
  3. C) z, y, x
  4. D) x, z, y
  5. E) z, x, y

Answer:  A

Var: 1

13) A 9 V battery is hooked up to two resistors in series. One has a resistance of 5 Ω, and the other has a resistance of 10 Ω. Several locations along the circuit are marked with letters, as shown in the figure. Which statement is true?

 

  1. A) The current at A is equal to the current at B, which is equal to the current at C, which is equal to the current at D.
  2. B) The current at A is greater than the current at B, which is equal to the current at C, which is greater than the current at D.
  3. C) The current at A is greater than the current at B, which is greater than the current at C, which is greater than the current at D.

Answer:  A

Var: 1

 

14) A 9 V battery is hooked up to two resistors in series. One has a resistance of 5 Ω, and the other has a resistance of 10 Ω. Several locations along the circuit are marked with letters, as shown in the figure. Through which resistor is energy being dissipated at the higher rate?

 

  1. A) the 10 Ω resistor
  2. B) the 5 Ω resistor
  3. C) Energy is being dissipated by both resistors at the same rate.

Answer:  A

Var: 1

15) In the circuit shown, the resistor R2 is adjustable. As its resistance is made larger, the voltage at point A

 

  1. A) increases.
  2. B) decreases.
  3. C) does not change.

Answer:  B

Var: 1

 

16) Identical batteries are connected in different arrangements to the same lightbulb, as shown in the figure. For which arrangement will the bulb shine the least?

 

  1. A) w
  2. B) x
  3. C) y
  4. D) z

Answer:  B

Var: 1

 

17) A 9 V battery is hooked up to two resistors in series. One has a resistance of 5 Ω, and the other has a resistance of 10 Ω. Several locations along the circuit are marked with letters, as shown in the figure. If the voltage is zero at the negative terminal of the battery, the voltage at location B is

 

  1. A) greater than 4.5 V.
  2. B) less than 4.5 V.
  3. C) zero.
  4. D) 4.5 V.

Answer:  A

Var: 1

 

18) Identical batteries are connected in different arrangements to the same lightbulb, as shown in the figure. For which arrangement will the bulb shine the brightest?

 

 

 

 

  1. A) A
  2. B) B
  3. C) C

Answer:  C

Var: 1