Physics Exam: One-Dimensional Kinematics

A fullback is running down the football field in a straight line. He starts at the 0-yard line at 0 seconds. At 1 second, he is on the 10-yard line; at 2 seconds, he is on the 20-yard line; at 3 seconds, he is on the 30-yard line; and at 4 seconds, he is on the 40-yard line. What is the player's acceleration?

0 m/s

13. Olympic gold medalist Michael Johnson runs one time around the track - 400 meters - in 38 seconds. What is his displacement? ___________ What is his average velocity? ___________

0, 0m/s

T or F: An object with a negative acceleration will be represented on a position-time graph by a line which curves downwards.

False

T or F: An object with a positive acceleration will be represented on a position-time graph by a line which curves upwards.

False

T or F: If an object is at rest, then the position-time graph will be a horizontal line located on the time-axis.

False

T or F: Position-time graphs cannot be used to represent the motion of objects with accelerated motion.

False

T or F: The slope on a position-time graph is representative of the acceleration of the object.

False

T or F:A line with a negative slope on a velocity-time graph is representative of an object with negative velocity.

False

T or F:A line with zero slope on a velocity-time graph will be representative of an object which is at rest.

False

T or F:An accelerated object's motion will be represented by a curved line on a velocity-time graph.

False

T or F:An object which is slowing down is represented by a line on a velocity-time graph which is moving in the downward direction.

False

T or F:If an object changes its direction, then the line on the velocity-time graph will have a changing slope.

False

T or F:Objects with positive acceleration will be represented by upwardly-curved lines on a velocity-time graph.

False

T or F: A straight, diagonal line on a position-time graph is representative of an object with a constant velocity.

True

T or F: Accelerated objects are represented on position-time graphs by curved lines.

True

T or F: An object with a negative velocity will be represented on a position-time graph by a line with a negative slope.

True

T or F: An object with a positive velocity will be represented on a position-time graph by a line with a positive slope.

True

T or F:If an object is at rest, then the velocity-time graph will be a line with zero slope.

True

T or F:The area on a velocity -time graph is representative of the change in position of the object.

True

T or F:The slope on a velocity-time graph is representative of the acceleration of the object.

True

18. Which one of the following statements is NOT true of a free-falling object? An object in a state of free fall ____. a. falls with a constant speed of -10 m/s. b.falls with a acceleration of -10 m/s/s. c.falls under the sole influence of gravity. d. falls with downward acceleration which has a constant magnitude.

a

21. As an object freely falls, its ____. a. speed increases b. acceleration increases c. both of these d. none of these

a

If an object is moving eastward and slowing down, then the direction of its velocity vector is ____. a. eastward b. westward c. neither d. not enough info to tell

a

17. Which one of the following quantities is NOT a speed? a. 10 mi/hr, east b. 10 mi/hr/sec, west c. 35 m/s, north d. 20 m/s

b

26. When a rock is dropped, it will accelerate downward at a rate of 9.8 m/s2. If the same rock is thrown downward (instead of being dropped from rest), it acceleration will be ____. (Ignore air resistance effects.) a. less than 9.8 b. 9.8 c. more than 9.8

b

27. Consider drops of water that leak from a dripping faucet at a constant rate. As the drops fall they ____. a. get closer together b. get farther apart c. remain at a relatively fixed distance from one another

b

If an object is moving eastward and slowing down, then the direction of its acceleration vector is ____. a. eastward b. westward c. neither d. not enough info to tell

b

23. Ten seconds after being dropped from rest, a free-falling object will be moving with a speed of ____. a. about 10 m/s b. about 50 m/s c. about 100 m/s d. more than 100 m/s

c

24. A baseball pitcher delivers a fast ball. During the throw, the speed of the ball increases from 0 to 30.0 m/s over a time of 0.100 seconds. The average acceleration of the baseball is ____ m/s2. a. 3 b. 30 c. 300 d. 3000 e. none

c

25. On takeoff, a rocket accelerates from rest at a rate of 50.0 m/s2 for exactly 1 minute. The rocket's speed after this minute of steady acceleration will be ____ m/s. a. 50 b. 500 c. 3 x 10^3 d. 3.60 X 10^3 e. none

c

A fullback is running down the football field in a straight line. He starts at the 0-yard line at 0 seconds. At 1 second, he is on the 10-yard line; at 2 seconds, he is on the 20-yard line; at 3 seconds, he is on the 30-yard line; and at 4 seconds, he is on the 40-yard line. This is evidence that a. he is accelerating b. he is covering a greater distance in each consecutive second c. he is moving with a constant speed (on avg)

c

If an object has an acceleration of 0 m/s2, then one can be sure that the object is not ____. a. moving b. changing position c. changing velocity

c

16. Which one of the following quantities is NOT a vector? a. 10 mi/hr, east b. 10 mi/hr/sec, west c. 35 m/s, north d. 20 m/s

d

28. Renatta Oyle is again found driving her '86 Yugo down Lake Avenue, leaving the following trail of oil drops on the pavement. If her car is moving from right to left, then ... a. her velocity has a rightward direction and her acceleration has a rightward direction. b. her velocity has a rightward direction and her acceleration has a leftward direction. c. her velocity has a leftward direction and her acceleration has a rightward direction. d. her velocity has a leftward direction and her acceleration has a leftward direction.

d

If car A passes car B, then car A must be ____. a. accelerating b. accelerating at a greater rate than car B c. moving faster than car B and accelerating more car B d. moving faster than car B, but not necessarily accelerating

d

Which one of the following is NOT consistent with a car which is accelerating? a. a car is moving with an increasing speed b. a car is moving with a decreasing speed c. a car is moving with a high speed d. a car is changing direction

d