Physics AP Name

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Physics AP
Chapter 2
Mr. Roy
Name ____________________________
Date _____________________________
Period ___________________________
Multiple Choice (3 pts. each)
__c__ 1. When is the average velocity of an object equal to the instantaneous velocity?
a. always
b. only when the velocity is increasing at a constant rate
c. only when the velocity is constant
d. never
___a_ 2. Suppose that a car traveling in a (-) direction begins to slow down as it approaches a traffic light.
Make a statement about its acceleration.
a. The car is decelerating and its acceleration is positive.
b. The car is decelerating and its acceleration is negative.
c. The acceleration is zero
d. A statement cannot be made using the information given.
__b__ 3. Objects A and B both start at rest. They both accelerate at the same rate. However, object A
accelerates for the twice the time of object B. What is the final speed of object A compared to that of
object B?
a. the same speed
b. twice as fast
c. three times as fast
d. four times as fast
___d_ 4. Objects A and B both start at rest. They both accelerate at the same rate. However, object A
accelerates for the twice the time of object B. What is the distance traveled by object A compared to
that of object B?
a. the same distance
b. twice as far
c. three times as far
d. four times as far
__b__ 5. Suppose a ball is thrown straight up. Make a statement about the velocity and the acceleration
when the ball reaches the highest point.
a. Both its velocity and its acceleration are zero.
b. Its velocity is zero and its acceleration is not zero.
c. Its velocity is not zero and its acceleration is zero.
d. Neither its velocity nor its acceleration is zero.
___a_ 6. Ball A is dropped from the top of a building. One second later, ball B is dropped from the same
building. As time progresses, the distance between them
a. increases
b. remains constant
c. decreases d. cannot be determined
__c__ 7. An object is moving with constant non-zero velocity in the + x axis. The position versus time graph
of this object is:
a. a horizontal straight line
b. a vertical straight line
c. a straight line making an angle with the time axis
d. a parabolic curve
__c__ 8. The area under a curve in a velocity versus time graph gives :
a. acceleration
b. velocity
c. displacement
d. position
__c__ 9. If the position versus time graph of an object is a horizontal line, the object is :
a. moving with constant non-zero speed
b. moving with constant non-zero acceleration
c. at rest
d. moving with infinite speed
__b__ 10. Suppose that an object is moving with constant acceleration. Make a statement concerning its
motion with respect to time.
a. In equal times its speed increases by equal amounts.
b. In equal times its velocity changes by equal amounts.
c. In equal times it moves equal distances.
d. A statement cannot be made using the information given
Graphical Analysis
Using the provided graph below, answer questions 11 – 13. (5 pts. each)
10
11. What is the average velocity between
8
time = 4.0 s and time = 12.0 s?
__vavg = -0.5 m/s___
6
12. What is displacement between time =
4
4.0 s and time = 18.0 s?
x (m)
2
__x = 3.0 m___
13. What is the average velocity between
time = 0 s and time = 8 s ?
0
-2
___ vavg = 0.4 m/s ___
-4
14. What is the average velocity between
time = 9.0 s and time = 14.0 s?
__ vavg = 3.0 m/s ___
10
15. What is displacement between time =
4.0 s and time = 14.0 s?
6
__17.5 m____
16. What is the average acceleration
between time = 0 s and time = 9 s ?
__0.6 m/s2__________
0
2
4
6
8
10 12
time (sec)
14
16
18
0
2
4
6
8
10 12
time (sec)
14
16
18
8
4
v(m/s)
2
0
-2
-4
Problems (20 pts each)
1. A train 400 m long is moving on a straight track with a speed of 82.4 km/hr. The engineer applies
the brakes at a crossing causing constant deceleration and later the last car passes the crossing with
a speed of 16.4 km/hr. Determine how long the train blocked the crossing. Disregard the width of
the crossing.
(82.4 km/hr)(1000m/km)(1hr/3600sec) = 22.9 m/s
Vo = 22.9 m/s
Vf = 4.56 m/s
x = 400 m
t=
a = (4.56)2 – (22.9)2
2(400)
(16.4 km/hr)(1000m/1km)(1hr/3600sec)= 4.56 m/s
4.56 – 22.9
-0.63
= 29.1 sec
= -0.630 m/s2
2. An arrow is shot directly into the air with a speed of 100.0 m/s. If friction is neglected, how high will the
arrow travel into the air? How long will the arrow be in the air?
Vo = 100 m/s
Vf = 0 m/s
g = - 9.80 m/s2
y = (0 2 – 100 2) = 510 m
2(-9.80)
tup = tdown = 0 – 100
-9.8
= 10.2 sec
ttotal = 2(10.2) = 20.4 sec
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