Worksheet: Motion Problems
KEY
Name___________________
1. A car with a velocity of 22 m/s is accelerated uniformly at the rate of 1.6
m/s2 for 6.8 s. What is its final velocity?
m
s
v f = vi +at = 22
+ (1.6
m
s2
6.8 s ) = 33
m
s
2. Light travels in a straight line at a constant speed of 3.0 x 10 8 m/s for 4.1
years to reach the earth from the nearest star 3.9 x 10 13 km away. What is
its acceleration?
To be answered in Episode 303
3. A boy sliding down a hill accelerates at 1.40 m/s2. If he started from
rest, in what distance would he reach a velocity of 7.00 m/s?
v f 2 = 2ad
vf 2
(7.00 ms )2
d=
=
= 17.5 m
2a
2 1.40 sm2
4. What is the acceleration of a plane that changes velocity from 75 m/s to
140 m/s in 15s? How far does a plane fly during that time?
v f = vi + at
a=
v f - vi
t
=
140
m
s
- 75
15 s
m
s
= 4.3
m
s2
To solve for “d”, you must use the value of “a”determined in part 1.
vf
2
d=
2
= vi + 2ad
vf
2
- vi
2a
2
(140 m s ) 2 (75 m s ) 2

1600 m
2(4.3 m s 2 )
PHYSICSFundamentals
2004, GPB
3-14a
5. If a bullet leaves the muzzle of a rifle with a speed of 600 m/s, and the barrel
of the rifle is 0.9 m long, at what rate is the bullet accelerated while in the
barrel?
v f 2 = 2ad
vf 2
(600 ms )2
a=
=
= 2 10 5
2d
2 0.9 m
m
s2
6. A car is traveling at a velocity of 22 m/s when the driver puts on the brakes
to decelerate it at 1.4 m/s2 over a distance of 110 m. What is the car’
s
velocity at the end of this distance?
To be answered in Episode 303
7. A ball, originally at rest, undergoes a constant acceleration of 0.76m/s2.
How long does it take the ball to travel 4.8m?
d=
t=
1
2
at 2
2d
=
a
2(4.8 m)
= 3.6 s
0.76 sm2
8. You are driving your car down a straight road at a constant speed of 23 m/s
(about 50 mi/h). What is your acceleration? _______________
a. Suddenly you see a stalled school bus across the road ahead. It takes
you 0.75 s to react and put on the brakes. How far does the car move
during this time?
b. When you apply the brakes, the car decelerates at 6.2 m/s2. How far
does the car travel until it comes to a stop?
c. If the bus is 62 m away, will you be able to stop before hitting it?
a.
v=
d
t
d = vt = (23
b.
m
s
2
2
)(0.75 s) = 17 m
d=
c.
2
v f = vi + 2ad
v f - vi
2a
d total = d a + d b = 17 m + 43 m = 60 m
You would be able to stop in time.
PHYSICSFundamentals
2004, GPB
3-14b
2
(0 m ) 2 (23 m s ) 2
 s
43m
2(6.2 m s2 )