Review Questions: Equations of Motion (Kinematics)
1.
A briefcase is sitting on the floor of an elevator that is going up at a speed of 3.0 m/s.
Because of a mechanical failure, the elevator stops instantly and the briefcase rises from
the floor of the elevator.
To what height above the floor does the briefcase rise?
2.
A ball is dropped from the roof of a building. The ball takes 4.0 seconds to reach the
ground. Because of air friction, the ball falls with an average acceleration of 6.8 m/s2.
What is the height of the building?
3.
An airplane flew between Montreal and Vancouver with two stopovers; one in Toronto
and the other in Calgary. The following table shows the distances travelled as well as the
flight and stopover times.
Montreal - Toronto Flight
Stopover in Toronto
Toronto - Calgary Flight
Stopover in Calgary
Calgary - Vancouver Flight
Distance
(km)
Time
(h)
530
0
3210
0
700
0.67
1.00
4.33
1.00
0.80
What was the airplane’s average speed during the trip?
4.
A student conducts a free-fall experiment while standing on the edge of the school roof
12.0 m above the ground. The student throws a heavy ball vertically upwards at a velocity
of 5.00 m/s. On its way down, the ball narrowly misses the roof and hits the ground.
How long does it take the ball to hit the ground from the instant it is released?
5.
A cyclist travelling along a bicycle path accelerates at a rate of 1.0 m/s 2 for 4.0 seconds.
During this time, she travels a distance of 20 metres.
What was the velocity of cyclist after the 4.0 seconds of acceleration?
6.
An automobile, accelerating at a rate of 3.00 m/s2, increases its velocity from 10.0 m/s to
22.0 m/s.
What distance did it travel during this time?
7.
Laura propels a stone straight up with her slingshot. The stone strikes a tree branch 4.0 m
above her. It strikes the branch with a velocity of 5.0 m/s.
How long does this take?
8.
Titov and Dimitri are travellers on the Siberian Railway. Titov’s train leaves Irkutsk for
Krasnoyarsk travelling at an average speed of 42.0 m/s. Dimitri’s train leaves
Krasnoyarsk 30 minutes later heading towards Irkutsk on a parallel track and travelling at
an average speed of 28.0 m/s. Titov’s train travels for 5.00 hours before meeting
Dimitri’s train.
What is the distance in kilometers between the two cities?
9.
A student conducts a free-fall experiment while standing on the edge of the school roof
12.0 m above the ground. The student throws a heavy ball vertically upwards at a velocity
of 5.00 m/s. On its way down, the ball narrowly misses the roof and hits the ground.
How long does it take the ball to hit the ground from the instant it is released?
10.
The highway code states that a car moving at 20.0 m/s must be able to stop within a
distance of 50.0 metres.
Within what distance must a car travelling at 40.0 m/s be able to stop if we assume
that it can slow down at the same rate?
11.
A stone is thrown vertically upward with a velocity of 30 m/s.
How much time does it take for the stone to hit the ground?
12.
A stone is dropped down a well. The splash is heard 3.0 seconds later.
How deep is the well?
13.
From the roof of a building which is 50 metres high, a stone is thrown vertically
downward. It takes 5 seconds for it to reach the ground.
With what velocity was the stone thrown?
14.
On the moon, where the acceleration due to gravity is 1.6 m/s2, an astronaut drops a
hammer from a height of 1.8 m above the ground.
From the time he lets go of the hammer, how much time does it take for it to hit the
ground?
15.
A cyclist travelling along a bicycle path accelerates at a rate of 1.0 m/s2 for 4.0 seconds.
During this time, she travels a distance of 20 metres.
What was the velocity of cyclist after the 4.0 seconds of acceleration?
16.
During a Quidditch match, Potter and Malfoy are chasing the snitch. Trying to catch the
snitch first, Malfoy dives off his broom at 2 m/s [Down], from a height of 20 m from the
snitch, while Potter is racing towards the snitch at a constant speed of 25 m/s for 75 m.
Who will make it to the snitch first and with how much time to spare?
(Assume the snitch is at rest.)
17.
From rest, a ball rolls down a 1.0 m long hill accelerating at a rate of 4.0 m/s2. It then
continues smoothly at a constant speed over a flat surface for 5.0 seconds. Ignore the
effects of friction.
V1 = 0 m/s
a = 4.0 m/s2
1.0 m
?
5.0 seconds
How far does the ball travel along the flat surface?