Name________________________________________ Date_______________ Period_______
Kibala CP Physics
Section 4 Free Fall/Horizontal Projectile Motion
Dropped Objects Problem Set
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1) A cannonball is dropped off the Leaning Tower of Pisa. It takes the
cannonball 3.38 seconds to hit the ground. How high is the leaning tower?
How fast is the cannonball traveling right before it hits the ground?
2) A stone is dropped from a cliff. It hits the ground below after 3.25 s. How
high is the cliff? How fast is the object going just before it strikes the ground?
3) A window washer is curious how high above the ground he is so he drops his
squeegee and times its flight to the ground. He counts 5 seconds for the
squeegee to reach the ground. In his head he does a quick calculation to find
out how high he is. How high is he?
4) A penny is dropped off of the empire state building’s top floor which is 373 m
above the ground. How long should it take the penny to reach the ground?
How fast should the penny be traveling just before it hits the ground?
Multiply your speed by 2 to get its speed in mph. Do you really think it is
traveling this fast? Explain.
5) I drop my phone out of my pocket which is .9 m above the ground. How long
will it take my phone to hit the ground? How fast will the phone be traveling
just before it touches the ground?
6) On September 26, 1993, Dave Mundy went over the Canadian edge of Niagra
Falls in a steel ball equipped with an air hole and then fell 48 m to the water
(and rocks). How long was Mundy falling before he hit the water? How fast
was Mundy traveling?
7) A falcon will free fall to catch a fish right below it. If the falcon drops 76m
below its initial position in the air how long will it take the falcon to catch its
meal? What is the falcon’s speed just before it pulls up to catch the fish?
8) A flower pot falls from a windowsill 25 m above the sidewalk. How long does
it take the flower pot to reach the ground? How fast is the flower pot moving
when it strikes the ground?
9) A wrench is dropped on the moon where the acceleration due to gravity is
1.6 m/s2. If it is dropped from a 2m height how long does it take the wrench
to hit the ground? How fast is the wrench moving when it hits the ground?
10)A wrench is dropped on Jupiter which has no solid surface and has
acceleration due to gravity of 24.5 m/s2. How far does the wrench travel
after 5 seconds of fall? How fast is the wrench moving after 5 seconds?
Answers:
1) 55.98 m, 33.124 seconds
2) 51.76 m, 31.85 m/s
3) 122.5 m
4) 8.72 seconds, 85.5 m/s, 171 mph
5) .43 seconds
6) 3.13 seconds, 30.67 m/s
7) 3.94 seconds, 38.60 m/s
8) 2.26 sec, 22.13 m/s
9) 1.58 sec, 2.53 m/s
10)306.25 m, 122.5 m/s