Section 3.3
Free Fall
Practice Test
1.
A tennis ball is dropped from 1.5 m above the ground, touches the ground for 0.008 s and rebounds to a height of 0.75 m. What is the ball's velocity when it hits the ground?
a.
-3.8 m/s
b.
3.8 m/s
2
c.
-5.4 m/s
2
d.
-5.4 m/s
Hint
2.
A 75-kg swimmer steps off a 10.0-m tower. What is the swimmer's velocity on hitting the water?
a.
0.25 m/s
b.
-14.0 m/s
c.
38.3 m/s
d.
27.1 m/s
Hint
3.
What is a rope's velocity 4.0 s after being dropped from a hovering helicopter?
a.
-2.0×10
1
m/s
b.
4.0×10
1
m/s
c.
-4.0×10
1
m/s
d.
-4.0×10
2
m/s
Hint
4.
A ball falls freely from rest for 15.0 s. Calculate the ball's velocity after 15.0 s.
a.
-78 m/s
b.
147 m/s
c.
-147 m/s
d.
78 m/s
Hint
