Physics Kinematics Set #2
w/ Freefall
(
remember: velocity

time graphs and other
“pictorial illustrations” are your friends)
1.
A hummer slows down uniformly from 21 m/s to rest in 220m. How long does it
take it to stop?
2.
A ball is falling at 20 m/s just be
fore it strikes the floor. It leaves the floor at a
speed of 16 m/s traveling up. Find the ball’s average acceleration if the collision
lasts 0.04 sec.
3.
A boy sledding down a hill accelerates at 1.4m/s/s/. If he started from rest, in what
distance would he
reach 7.0 m/s?
4.
A worker drops a wrench from the top of a tower 80m tall. With what velocity
does the wrench strike the ground?
5.
A physics student throws a cat straight up into the air. The cat is in the air for 4
sec. before it was caught at its original
position.
a.
What was the initial velocity of the cat?
b.
How high did the car rise in the air?
6.
A small first

aid kit is dropped by a rock climber who is descending steadily at
1.9 m/s. After 2.5sec, what is the velocity of the first

air kit, and how far is t
he kit
below the climber?
7.
A small fish is dropped by a pelican that is rising steadily at 0.50 m/s.
a.
After 2.5 sec, what is the velocity of the fish?
b.
How far below the pelican is the fish after 2.5 sec?
8.
An armadillo is thrown upward at 35 m/s. How far wi
ll it travel during the next 2
sec?
9.
Ranger Rick in Death Valley National Park is driving at 56 km/hour when a gila
monster jumps onto the road 65m ahead of the car. After a reaction time of t sec,
the ranger applies the brakes to produce an acceleration o
f

3.0m/s/s. What is the
maximum reaction time allowed if the ranger is to avoid hitting the monster?
Answers:
1) 20.9m 2) a = 900m/s/s 3) d = 17.5m 4) v = 40m/s 5) a) v=20m/s b) d=20m
6) v = 27m/s d = 31m 7) v = 24.5 m/s 8) d = 50m
9) t = 1.6 sec
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