Worksheet 4 - Kinematics Equations
1.
Police forensics visit the scene of an accident in which a car skidded into an intersection
after failing to stop for a red light. The skid marks left by the vehicle in question was
30.0 m long. Forensics also determined that the car’s deceleration, with the brakes fully
applied, had a magnitude of 6.0 m/s2. If the posted speed limit was 65 km/h, was the
motorist speeding prior to applying the brakes?
2.
An airplane is already moving at 12.0 m/s when it enters a 500.0 m long stretch of
runway. At that instant, the pilot engages the engines to full thrust and gives the
airplane a 2.36 m/s2 acceleration.
(A)
(B)
3.
A car moving with a constant acceleration covers the distance between two points 60.0 m
apart in 6.0 s. Its velocity as it passes the second point is 15.0 m/s.
(A)
(B)
(C)
4.
If the airplane needs to be travelling at 45 m/s or more to lift off successfully,
will the airplane lift off? Show why or why not?
How long will it take the airplane to reach the end of this stretch of runway?
What was the speed at the first point?
What is the constant acceleration?
How far behind the first point was the car at rest?
Andrew and Sarah ran down the hill. Both started from rest and accelerated steadily.
Andrew accelerated at 0.25 m/s 2 and Sarah at 0.30m/s2. After running for 20.0 s, Sarah
fell down.
(A)
(B)
(C)
(D)
How far did Sarah run before she fell down?
How far had Andrew travelled when Sarah fell?
How fast was Andrew running when Sarah fell?
How long (to the nearest second) was it after Sarah fell that Andrew ran into her
and broke his crown?
5.
A ski-doo moving at 12 m/s [W] accelerates at 6.0 m/s2 [W]. How long will it take to
experience a displacement of 63 m [W]?
6.
On a 150 m straight sprint, a cyclist accelerates from rest for 4.5 s at 3.8 m/s2. How
long will it take her to complete the 150 m track, assuming she maintains her speed for
the remaining part of the track?
7.
A sprinter who is running a 250 m race accelerates from rest at 7.5 m/s2 for 1.2 s and
maintains this speed for the remainder of the race. What is her time for the race?
8.
A car moves at 12 m/s for 30.0 seconds. It then accelerates at 1.5 m/s2 for 8.00 seconds.
Finally, it continues on at this top speed for another 12.0 seconds. Calculate the net
displacement during the whole time interval.
9.
A rocket sled accelerates from rest for a distance of 645 m at 16.0 m/s2. A parachute
is then used to slow it down to a stop. If the parachute gives the sled an acceleration of
-18.2 m/s2 and there is 500.0 m of sled track remaining after the shoot opens, will the
sled stop before running off the track? Show why or why not?
10.
Superman is flying at an initial velocity of 33.5 m/s [N] when he decides to slow to
10.0 m/s [N] in a time of 8.05 s. He then continues at this velocity for 12.4 s before
accelerating at 2.35 m/s2 [N] until he reaches a final velocity of 23.8 m/s [N].
(A)
(B)
11.
Two cars accelerated uniformly from a stationary start on a straight racing track, Car A at
2.5 m/s2, and Car B at 2.0 m/s2.
(A)
(B)
12.
Calculate Superman’s displacement in this time. (Hint: This motion has three
unique parts)
Calculate Superman’s average velocity for his entire flight.
At what time where the cars separated by 25 m?
What was the speed of car A at the instant that the speed of car B was 14 m/s?
A police car stopped at a set of lights has a speeder pass it at 100.0 km/h. If the police
car can accelerate at 3.6 m/s2,
(A)
(B)
(C)
how long does it take to catch the speeder?
how far would the police car have to go before it catches the speeder?
what would be its speed when it caught up with the speeder? Is this speed
reasonable?