Chapter 2: Motion

D. in region D

The speed of the object is largest A. in region A. B. in region B. C. in region C. D. in region D. E. in region E

C. can change direction.

1. A car traveling at constant speed A. does not turn. B. travels more distance in a second the longer the car travels. C. can change direction. D. cannot be going uphill.

C. 300s

1. A woman walks a distance of 360 m with an average speed of 1.2 m/s. What time was required to walk this distance? Give your answer in seconds. A. 360s B. 432s C. 300s D. 124s

B. 5 m/s2 .

10. In order to go from rest to 50 m/s in 10 s, a jet must be able to accelerate at A. 2 m/s2 . B. 5 m/s2 . C. 20 m/s2 . D. 50 m/s2 .

C. 4.3 km

2. A hiker walks an average speed of 1.2 m/s. What distance in kilometers does the hiker travel in a time of one hour. A. 1.2 km B. 5 km C. 4.3 km D. 10 km

D. 360 mi.

2. If your average speed for a 6 hr trip is 60 mi/hr, the distance traveled is A. 10 mi. B. 60 mi. C. 120 mi. D. 360 mi.

A. 1/3 block/min

2.1 Ben leaves his home and walks to the bank, then back home in a total of 30 minutes. What is his average speed? A. 1/3 block/min B. 0 blocks/min C. 1/6 block/min D. 10 blocks/min

B)The velocity of the car.

2.10 A car is traveling on an interstate where north is taken to be the positive direction. A graph of the distance it has moved as a function of time is shown. What is the physical significance of the slope? A)The distance the car has moved. B)The velocity of the car. C)The acceleration of the car

B. It slows down all the time.

2.11 The graph for position vs. time is given for a car. What can you say about the velocity of the car over time? A. it speeds up all the time B. it slows down all the time C. it moves at constant velocity D. sometimes it speeds up and sometimes it slows E. not really sure

C. Subtracting area 2 from area 1

2.12 The graph represents the velocity of a car over time. Where the car ends up, relative to its starting point, can be found by A. adding the slopes of each section of the graph. B. adding area 1 to area 2. C. subtracting area 2 from area 1. D. subtracting area 1 from area 2.

B. it is not moving

2.13 The graph of position vs. time is given for a train. What can you say about the train's motion from time t1to time t2? A. it is moving with constant velocity B. it is not moving C. it is moving with a constant negative velocity D. it is accelerating

C

2.14 In which of these v vs. t graphs is the acceleration changing?

A. A car starts from rest and accelerates. It then travels at a constant velocity before slowing to a stop

2.15 Which scenario is portrayed by the graph? A. A car starts from rest and accelerates. It then travels at a constant velocity before slowing to a stop. B. A car starts from rest and moves forward. It stops for a while before returning to its starting position. C. A car travels at a constant velocity, then accelerates for a while, then returns to its initial constant velocity.

B

2.16 Which graph shows an object moving with a constant non-zero acceleration?

B)Speed is a scalar and velocity is a vector.

2.2 What is the difference between velocity and speed? A)There is no difference, they are both vectors. B)Speed is a scalar and velocity is a vector. C)Speed is a vector and velocity is a scalar. D)There is no difference, they are both scalars.

B. No

2.3 If the average velocity is non-zero over a time interval, does this mean that the instantaneous velocity is never zero over that same time interval? A. Yes B. No

A. Yes. Velocity has both a magnitude (speed) and a direction. If the direction changing there is an acceleration.

2.4 Can a car be accelerating when its speed is constant? A)Yes. Velocity has both a magnitude (speed) and a direction. If the direction is changing there is an acceleration. B)No. If speed is constant there is no change so therefore no acceleration. C)No. Acceleration is the rate of change of velocity. If the speed is constant the velocity is not changing. D)Yes. Acceleration and speed are not related, so a constant speed has no effect on acceleration.

A. Yes.

2.5 If the velocity of an object is non-zero, can the acceleration of the object be zero? A. Yes B. No

Graph B

2.8 Which graph shows an object moving with a constant non-zero velocity?

Graph A

2.9 Which graph shows an object moving with a constant non-zero velocity?

A. speed.

3. A quantity that is a measure of how the distance traveled changes with time is A. speed. B. force. C. acceleration. D. momentum. E. velocity.

D. 21 m/s

3. Starting from rest, a car accelerates at a rate of 4.2 m/s2 for a time of 5 seconds. What is its velocity at the end of this time? A. 19 m/s B. - 19 m/s C. -21m/s D. 21 m/s

D. -2.5 m/s2

4. A car is traveling at the velocity of 20 m/s on a flat road when it reaches the bottom of a hill. It coasts up the hill, coming to rest in 8 seconds. The average acceleration of the car while on the hill is A. 10 m/s2 . B. 2.5 m/s2 . C. 0 m/s2 . D. -2.5 m/s2. E. -10 m/s2 .

A. 5.3 m/s

4. A runner traveling with an initial velocity of 2 m/s accelerates at a constant rate of 1.1 m/s2 for a time of 3 seconds. What is his velocity at the end of this time? A. 5.3 m/s B. 6 m/s C. 3.3 m/s D. 2.2 m/s

C. 10.95 m

5. A runner traveling with an initial velocity of 2 m/s accelerates at a constant rate of 1.1 m/s2 for a time of 3 seconds. What distance does the runner cover during this process ? A. 6.95 m B. 12.95 m C. 10.95 m D. 8.95 m

B. 0.25 m/s2

5. A student releases a ball from rest on an inclined plane and measures that it travels a distance of 0.5m in a time of 2.0 s. The acceleration of the ball is A. 0.125 m/s2. B. 0.25 m/s2 . C. 0.5 m/s2 . D. 1.0 m/s2.

A. 16 m/s

6. A car moving with an initial velocity of 28 m/s slows down at a constant rate of −3 m/s2. What is its velocity after 4 seconds of deceleration? A. 16 m/s B. 28 m/s C. -12 m/s D. 6 m/s

B. the instantaneous velocity is positive but decreasing.

6. The acceleration of a body cannot be zero at a point where A. the instantaneous velocity is zero. B. the instantaneous velocity is positive but decreasing. C. the average velocity is positive. D. none of these.

C. negative.

9. For the entire motion, the average velocity is A. positive. B. zero (it is not moving). C. negative. D. It is not possible to tell from the graph.

Graph A

2.7 Which graph shows an object standing still?

D. 88 m

7. A car moving with an initial velocity of 28 m/s slows down at a constant rate of −3 m/s2. What distance does the car cover in this 4 second? A. 8 m B. 28 m C. 84 m D. 88 m

B. zero (it is not moving).

7. Refer to the graph above. The velocity of this object at the start of the motion is A. positive. B. zero (it is not moving). C. negative. D. It is not possible to tell from the graph.