Constant Acceleration Problems
(HS5.1.1.5, HS5.1.1.6, HS5.1.2.1, HS5.1.2.4, HS1.6.4)
Use the kinematics equations below to solve the problems given below. Be sure to use good problemsolving strategy by listing your data, choosing an appropriate tool (equation) to use, substituting your
data into the equation, and giving your answer with correct units. Show all your work on this sheet.
d = (vo + vf) t
2
a = (vf - vo)
t
Example: A car traveling at 20 m/s slows to a stop in 5 seconds. What was its acceleration?
Step 1:
Step 2:
Step 3:
d
=
List data
Choose an
Substitute
a=?
Equation ...
and solve…
t = 5 sec
a = (vf - vo)
a = 0m/s-20m/s = - 4 m/s2
vo = 20 m/s
t
5 sec
vf = o m/s
1. Why is the acceleration in the example negative?
Speed
decreases
2. What is the distance gone by the car in the example above before it comes to a stop?
50 m
3. How much time does it take for a cheetah to accelerate at 20 m/s2 from rest to a speed
of 40 m/s?
2 sec
4. What distance will the cheetah travel while accelerating to this speed?
40 m
5. A jet plane lands on a runway, coming to a stop in 40 seconds with a deceleration of
5 m/s2. What was its landing speed?
200 m/s
6. How long does the runway have to be for the landing of the jet in problem 5?
4000 m
7. A shark swimming in the ocean sees a passing fish swimming by and accelerates at
2 m/s2 to a speed of 20 m/s to overtake it, doing so in 3 seconds. What was the shark’s
initial speed?
14 m/s
8. How far did the shark of problem 7 swim in pursuit of the fish before overtaking it?
51 m
9. If the shark accidentally swims over a cliff and freefalls, how long will it take to reach a
speed of 49 m/s?
5 sec
10. How far will the shark have fallen to reach a speed of 49 m/s?
-122.5 m
11. A startled cat leaps straight up into the air, coming to rest briefly before falling back
down. If the round trip took 3 seconds, with what speed did the cat leave the ground?
14.7 m/s
12. To what height did the cat of problem 11 rise before falling back down?
11 m
13. A glass falls off a table top and hits the ground at 5.4 m/s. How much time does it take
to hit the ground below?
0.55 sec
14. How tall is the table in problem #13?
1.48 m
15. A ball is shot straight up into the air at an initial speed speed of 100 m/s. What is its
velocity (speed and direction) 15 seconds later?
16. How much time did the ball in problem 15 take to reach its maximum height?
- 47 m/s
downward
10.2 sec
17. What maximum height did the ball of problem 15 reach?
510 m
18. A stone is thrown straight down from a tall building at an initial speed of 30 m/s. A
short time later, it reaches the ground with a speed of 80 m/s. How long did it take to
reach the ground?
5.1 sec
19. How tall is the building of problem 18?
281 m
20. How long will an object be in the air if it is launched straight up at an initial velocity of
35 m/s and returns to the point of launch?
7.1 sec