Pre AP Physics Chapter 2: Motion in One Dimension

Multiple Choice (45)

Identify the letter of the choice that best completes the statement or answers the question. Carefully apply your answer choice to your scantron answer document.

1. Consider a velocity - time graph:

a.	slope tells you acceleration and area under the line tells you total time.	c.	slope tells you displacement and area under the line tells you nothing.
b.	slope tells you nothing and area under the line tells you displacement.	d.	slope tells you acceleration and area under the line tells you displacement

2. Note the figure. Describe the motion of the object graphed at point ‘A’.

a.	The acceleration of the object is zero.	c.	The velocity of the object is 9.8 m/s.
b.	The acceleration of the object is 9.8 m/s²	d.	The velocity of the object continues unaffected and unchanged.

3. How do you find acceleration from a graph?

a.	The area under the line of a p-t graph.	c.	The slope of a p-t graph.
b.	The area under the line of a v-t graph.	d.	The slope of a v-t graph.

4. Note the graph below. Which statement best describes the motion graphed?

a.	The object is moving away from the origin and then at 2 s the object turns and walks away from the origin.	c.	The object slows down to zero at 2 s and then speeds up again to 4 s.
b.	The object is moving towards the origin and then continues to walk past the origin, moving away from the origin.	d.	The object speeds up for two seconds and then slows down during th enext two seconds.

5. Consider a position - time graph:

a.	slope tells you acceleration and area under the line tells you total time.	c.	slope tells you velocity and area under the line tells you nothing.
b.	slope tells you nothing and area under the line tells you displacement.	d.	slope tells you acceleration and area under the line tells you displacement

6. How do you find displacement from a graph?

a.	The area under the line of a p-t graph.	c.	The slope of a p-t graph.
b.	The area under the line of a v-t graph.	d.	The slope of a v-t graph.

7. How do you find instantaneous velocity from a graph?

a.	The area under the line of a p-t graph.	c.	The slope of a p-t graph.
b.	The area under the line of a v-t graph.	d.	The slope of a v-t graph.

8. What is free fall acceleration?

a.	9.8 m/s² everywhere in the universe.	c.	9.8 m/s² anywhere on or around Earth.
b.	9.8 m/s² on Earth at sea level..	d.	9.8 m/s² for all falling objects.

9. What is the displacement of the object graphed?

a.	0 m	c.	40 m
b.	20 m	d.	80 m

10. Which statement best describes this graph?

a.	An object falling.	c.	An object falling, then rising.
b.	An object rising.	d.	An object rising then falling.

11. What happened when at the time when the object corssed the x axis?

a.	The object stopped moving.	c.	The object turned around.
b.	The object reached the origin.	d.	Nothing happened since the slope did not change.

12. A ball is thrown downward from the top of a tall cliff at 20 m/s. NAR (negating air resistance), what is the ball's acceleration as it falls?

a.	9.8 m/s²- 20 m/s	c.	20 m/s²
b.	9.8 m/s²	d.	9.8 m/s²+ 20 m/s

13. Consider the graph below. What can be calculated from the tangent line?

a.	Instantaneous velocity	c.	average velocity
b.	Instantaneous acceleration	d.	average acceleration

14. In what way is velocity different from speed?

a.	You can change your speed without changing your velocity.	c.	Speed has both magnitude and direction, velocity has only direction.
b.	You can change your velocity without changing your speed.	d.	Speed is a vector while velocity is a scalar.

15. In the SI system speed and velocity

a.	measure exactly the same thing.	c.	are measured in m/s.
b.	are both vectors.	d.	are measured in mi/h.

16. Which of these is an example of an object in free fall?

a.	a curve ball pitch	c.	a rocket blasting off into space
b.	a bird in flight	d.	a satellit orbiting Earth

17. Which graph shows an object that is slowing down as it moves away from the roigin

a.		c.
b.		d.

18. What is the displacement of the object graphed when t = 6s?

a.	0 m	c.	120 m
b.	60 m	d.	162.5 m

19. Which of these is a graph of an accelerating object?

a.		c.
b.		d.

20. An object is in free fall

a.	only if it is falling.	c.	only if gravity is the only force acting on it.
b.	only if only one force acts on it.	d.	only if air resistance is the only force acting on it.

21. Which of these is an object in free fall?

a.		c.
b.		d.

22. Note the graph below. At what point or points did the direction of the object change?

a.	point B	c.	points B and D
b.	point C	d.	points A, B, and D

23. Which of these is a graph of a stationary object?

a.		c.
b.		d.

24. Which is a graph of an object moving towards the origin?

a.		c.
b.		d.

25. Note the graph. During which time or times is the object slowing down?

a.	3-4, and 4-5	c.	0 to 2 and 5-6
b.	3-4 and 5-6	d.	0 to 2 and 4-5

Short Answer (130)

Answer the questions below on your own paper. Be sure your answers are in complete sentences. It is iomportant that you copy the figures on to your paper. All of these questions are in 'a', 'b', 'c' format and your answers must be as well. Each part of an 'a', 'b', 'c' formatted question is worth ten points.

26. Consider the graph below. Be sure to sketch this graph on your answer page.

a) If this were a graph of accelerated motion what variables should there be on the 'x' and 'y' axis?

b) If this were a graph of motion at a constant velocity what variables should there be on the 'x' and 'y' axis?

c) Which line represents the least acceleration and which line represents the greatest velocity? Explain how you know.

27. Consider a state of motion called free fall:

a) Explain how an object in free fall can be going upwards.

b) Explain how an object that is thrown across a classroom is in free fall.

c) Explain why a sheet of paper dropped to the floor is not in free fall.

d) Explain how an airplane coming in for a landing is not in free fall.

e) Explain why Earth is in free fall.

28. Note the figure.

a) During which timeinterval is the object's acceleration zero?

b) What happens at t = 6 s?

c) What is the displacement of the object at t = 6 s

d) What is the displacemetn of the object at t = 14 s

e) What is the magnitude of the acceleration of the object?

Pre AP Physics Chapter 2: Motion in One Dimension

Answer Section

MULTIPLE CHOICE

1. ANS: D

2. ANS: B

3. ANS: D

4. ANS: B

5. ANS: C

6. ANS: B

7. ANS: C

8. ANS: B

9. ANS: A

10. ANS: D

11. ANS: B

12. ANS: B

13. ANS: A

14. ANS: B

15. ANS: C

16. ANS: D

17. ANS: C

18. ANS: D

19. ANS: A

20. ANS: C

21. ANS: B

22. ANS: B

23. ANS: D

24. ANS: D

25. ANS: B

SHORT ANSWER

26. ANS:

a) If this were a graph of accelerated motion velocity should be on the 'y' axis and time shouild be on the 'x' axis.

b) If there were a graph of motion at a constant velocity position or displacement should be on the 'y' axis and time should be on the 'x' axis.

c) Line 'C' represents the least acceleration because it has the least slope. Lint 'A' has teh greatest velocity this is because line 'A' has the greatest slope.

27. ANS:

Considering free fall:

a) An object going upwards can be in free fall if the only force acting on it is gravity.

b) An object thrown across a room is in free fall because the only force acting on the object is gravity.

c) A sheet of paper dropped to the floor is not in free fall because there is a second force, air resistance, acting aganist the force of gravity.

d) An airplane coming in for a landing is not in free fall because gravity is not the only force acting on the plane. The plane has lift and thrust acting on it as well as gravity.

e) Earth is in free fall because the only force acting on Earth is the force of gravity of the sun.

28. ANS:

a) The object's acceleration is zero between zero and 6 s.

b) At t = 6 s the objects accelerates uniformally.

c) At t = 6 s the object's displacement is 42 m.

d) At t = 14 s the object's displacement is 158 m.

e) The acceleration of the object is (12 m/s - 7 m/s) / 8 s = 0.625 m/s²