When is the average velocity of an object equal to the instantaneous velocity?
only when the velocity is constant
only when the velocity is increasing at a constant rate
2. An object moving in the +x axis experiences
an acceleration of 2.0 m/s
. This means the object is
traveling at 2.0 m in every second.
traveling at 2.0 m/s in every second.
changing its velocity by 2.0 m/s.
increasing its velocity by 2.0 m/s in every second.
3. Suppose that a car traveling to
the West (
direction) begins to slow down as it approaches a traffic light. Make
a statement concerning its acceleration.
The car is decelerating, and its acceleration is positive.
The car is decelerating, and its acceleration is negative.
acceleration is zero.
A statement cannot be made using the information given.
If the velocity of an object is zero, does it mean that the acceleration is zero? Support your answer with an
no, and an example would be an object starting
no, and an example would be an object coming to a stop
yes, because of the way in which velocity is defined
yes, because of the way in which acceleration is defined
Can an object's velocity change direction when its acceleration is consta
nt? Support your answer with an
No, this is not possible because it is always speeding up.
No, this is not possible because it is always speeding up or always slowing down, but it can never turn
Yes, this is possible, and a rock thrown
straight up is an example.
Yes, this is possible, and a car that starts from rest, speeds up, slows to a stop, and then backs up is an
Objects A and B both start at rest. They both accelerate at the same rate. However, object A accelerate
twice the time as object B. What is the final speed of object A compared to that of object B?
the same speed
twice as fast
three times as fast
four times as fast
When an object is released from rest and falls in the absence of friction,
which of the following is true concerning
Its acceleration is constant.
Its velocity is constant.
Neither its acceleration nor its velocity is constant.
Both its acceleration and its velocity are constant.
Suppose a ball
is thrown str
aight up. Make a
statement about the velocity and the acceleration when the ball
reaches the highest point.
Both its velocity and its acceleration are zero.
Its velocity is zero and its acceleration is not zero.
Its velocity is not zero and its
acceleration is zero.
Neither its velocity nor its acceleration is zero.
Suppose a ball is thrown downward in the absence of air resistance. Make a statement concerning its
Its acceleration is constantly increasing.
Its acceleration i
Its acceleration is constantly decreasing.
Its acceleration is zero.
and show your work: Formula, Variables, Substitution, Answer w/ Units
If you are driving 72 km/h along a straight road and you look to the side for 4.0 s, how far do
you travel during this inattentive period?
A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. What is the average speed of
motorist for this trip?
An airplane increases its speed from 100 m/s to 160 m/s, at the average rate of 15 m/s
How much time does it take for the complete increase in speed?
A cart with an initial velocity of 5.0 m/s experiences a c
onstant acceleration of 2.0 m/s
What is the cart's displacement during the first 6.0 s of its motion
A bullet moving horizontally to the right (+
direction) with a speed of 500 m/s strikes a
sandbag and penetrates a distance of
10.0 cm. What is the average acceleration, in m/s
A jet fighter plane is launched from a catapult on an aircraft carrier. It reaches a speed of 42
at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant,
what is the length of the catapult?
An object is thrown upward with a speed of 14 m/s on the surface of planet X where the
to gravity is 3.5 m/s
. What is the speed of the object after 8.0 s
Human reaction time is usually greater than 0.10 s. If your friend holds a ruler between your
fingers and releases it without warning, how far can you expect the ruler to
fall before you
A ball is thrown downward from the top of a building with an initial speed of 25 m/s. It strikes
the ground after 2.0 s. How high is the building?
19. Study the d
a) What is the
velocity of the object at the following times, 1.0s, 2.5s, 4.0s and 5.5s?
b) What is the average velocity from 0 to 4 seconds?
c) What is the average velocity from 4 to 6 seconds?
d) Sketch the v
t graph for the object’s motion
20. Study the v
a) What is the acceleration at 1.0 s?
b) What is the acceleration at 3.0 s?
c) What is the object’s displacement from 0 to 2 seconds?
d) What is the object’s displacement from 2 to 4 seconds?
e) What is the object’s displacement
from 4 to 6 seconds?
f) What is the object’s displacement from 6 to 8 seconds?
g) What is the object’s displacement from 0 to 8 seconds?