VERTICAL PROJECTILE MOTION
Use g = -9.8 m/s
2
1. If an object is allowed to fall freely toward the earth, what will be its displacement
after 2.0 seconds?
2. What velocity will a freely falling object have after falling 80 metres?
3. If a ball is dropped from a tall building, it strikes the ground in 6.0
seconds. What is the height of the building?
4. A ball is thrown vertically downward from the top of a 200-metre cliff
at -15 m/s.
a) Calculate its velocity after 3 seconds
b) Calculate the time it takes to get to the ground.
c) Calculate its velocity at impact.
5. An object is thrown vertically down from a cliff at -30 m/s.
Find: a) Its displacement in the 2nd second of travel. (Hint: d2 - d1)
b) The height of the cliff if it reaches the bottom at t = 3.0 s.
6. A body is thrown up into the air with a vertical velocity of 50 m/s.
Find: a) Time of rise
b) Height of rise
c) Velocity 8.0 seconds after launch.
7. An object is thrown up into the air with a vertical velocity of 80 m/s.
Find: a) Time of rise
b) Height of rise
c) Time of flight
d) Velocity 10.0s after launch
8. When a stone is dropped into a well, it hits bottom in 2.50 seconds. How
deep is the well?
9. If you fall over the edge of the roof of your house, 3.00m above ground, with what
velocity will you strike the ground?
10. An object is projected downward off a 200 m high cliff with an initial velocity of
-30.0 m/s. Find: a) Velocity when it hits the ground
b) Time to hit the bottom (2 ways)
11. An object is projected up into the air with a vertical velocity of 45 m/s.
Calculate: a) Time of rise
b) Height of rise
c) Time of flight
d) Velocity after 7.00 seconds
12. A stunt man falls from the roof of an 8.00
metre high building, and free falls toward
the earth. Find:
a) Velocity at which he strikes the ground.
b) Time of fall.
13. If an object is allowed to fall freely toward
the earth, how far will it fall during the 3rd
second of time?
14. An object, projected downward from a window at -20.0 m/s strikes the ground in
3.00 seconds. How high was the window above the ground?
15. A ball is projected downward off a 105m high cliff with an initial velocity of
-20.0 m/s. Find: a) Velocity when it strikes the ground.
b) Time to hit bottom (2 ways)
16. A ball is throw vertically upward at the edge of a 120 metre cliff, at 25 m/s.
Find: a) Time of rise
b) Height of rise
c) Total time of flight
d) Velocity at impact
17. An object is projected vertically upward at 17 m/s, at the edge of a 40.0 m cliff as
shown. Find: a) Time of rise
b) Height of rise
c) Time of flight
d) Velocity at which it strikes the ground.
18. At the edge of a cliff an object is projected upward at 35 m/s. It hits the ground in
8.00 seconds. Find: a) Time of rise
b) Height of rise
c) Height of the cliff
19. A ball is projected vertically upward off the edge of a cliff at a velocity of 10.0 m/s.
The cliff is 40.0 m high. Find:
a) Time of rise
b) Height of rise (above cliff)
c) Time of flight
d) Velocity at which it strikes the ground.
ANSWERS:
1. –19.6 m
2. –39.6 m/s
3. 176.4 m
4. a) –44.4 m/s
b) 5s
c) –64 m/s
5. a) –44.7 m
b) –134.1 m
6. a) 5.1s
b) 127.5 m
c) –28.4 m/s
7. a) 8.2 s
b) 326.5 m
c) 16.4 s
d) -18 m/s
8. 30.6 m
9. -7.67 m/s
10. a) -69.4 m/s
b) 4.02 s
11. a) 4.6 s
b) 103.3 m
c) 9.2 s
d) –23.6 m/s
12. a) 12.5 m/s
b) 1.3 s
13. 24.5 m
14. 104.1 m
15. a) –49.6 m/s
b) 3s
16. a) 2.6 s
b) 31.9 m
c) 8.1 s
d) -55 m/s
17. a) 1.7s
b) 14.74 m
c) 5s
d) -32.3 m/s
18. a) 3.6 s
b) 62.5 m
c) 33.6 m
19. a) 1.02 s
b) 5.1 m
c) 4.1 s
d) –30.2 m/s