Name
Projectile Motion
PROJECTILE MOTION
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Date:
10
1. A ball rolls with a speed of 2 rn/s across a table top that is 1 meter above the floor. Upon reaching the
edge of the table, it follows a parabolic path to its landing spot on the floorilow far along the floor is this
spotfromthetable?
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2. A rescue pilot drops a survival kit while her plane is flying atan altitude of 2000 meters with a forward
veLocity of 100 rn/s. Ifair friction is disregarded, how far in advance of thestarving explorets’ drop zoneL
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shouldshecelease the package?
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3. A rifle is fired horizontally. The bullet is found to have traveled 200 meters. The rifle barrel is 1.90
meters from the ground. Disregarding air friction, at what speed must the bullet have been traveling as it
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4. Askierleavesthehorizoatalendofthe ranipwWa velocityof25 m/sandlandsl0 metezsfromthe
bofthramp.Howhighistheeadoftheranipabovethelandingarea?
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5. An astronautstands on the edge ofa lunar crater and throws a half-eaten Moon Pie® horizontally with a
velocityof 5.00 mIs. The floorofthe crater is 100 meters below the astronaut What horizontal distance
will the Moon Pie® travel before hitting the floor ofthe crater? (Remember that the acceleration due to.
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gravity on the moon is only 1/6 of that on eatth.)
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1989 J. Wçston Walch, Publishcr
Physics Compu-Sheeff
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PROJECTILE MOTION PRACTICE.
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11
7
1. Stefan kicks a soccer ball off a cliff with ahorizonLx,eed of 15 m/s. If it
lands 28 meters from the base of the cliff, how high is the cliff?
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2. Natalie accidentally shoves a small rock off a cliff that is 45 meters high.
If it lands 62 meters from the base of the cliff; what was the original horizonta’
viocity with which It left the cliff?
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3. John kicks a football (exactly horizontally) off the bleachers. It reaches the
ground in 1.7 seconds. How high are the bleachers?
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4. Alex is waiting for a package to be dropped from an airplane. She calculates
where to stand (300 meters ahead of the drop location.) If t4e package lands
in 5.4 seconds (ignore air resistance!), what was, the horizontal speed of the
airplane?
5 Mike is running to catch a ball that was thrown from the top of a hill (from a
height of 16 meters). If the bail was thrown with a horizontal speed of 11 m/s,
how far from the foot of the hill should Mike stop iiiiining and catciiiff.
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6.
a stick of gum to her friend when she is on a cheerleader’s shoulder.
end catches it in 0.2 seconds, how high was Erica? Assume she threw the
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7. Scott throws a baseball. with a horizontal velocity of 7.8mJs. If he throws it off
a tower that is 23 meters high, how far from the base of the tower will it land?
8. While in Minnesota, Mei Mei throws a snowball (horizontally, of course) from
the top of a snow fort that is 4.5 meters high. If it bits her friend (who is 10 meters
away) iconds, with what speed did she throw the ball?
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9. While working at the country club, Ted almost gets hit by a golf ball that was hit
from the top of a knoll (height = 3.1 meters). He was 57 meters away, so he can
use his awesome knowledge of physics to calculate that the horizontally projected
golf ball had a speed of________________
10. Arya is on the Golden Gate Bridge when he notices a tourist throw a film canister
horizontally off the bridge with a speed of 14 rn/s. At that points the bridge is 63
barge with its midpoint 85 meters from the base of the
bridge, will the canister land on the barge or fall in the water? (Assume the barge
is 20 meters long.)
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Horizontally Launched Projectile Motion Quiz (E)
Name
Period
Equations:
x = vx t
y
Date________
5t
10 t
1. When an object is in projectile motion, it is accelerating
a. in both the horizontal and vertical directions
b. in the horizontal direction only
(Elivrtical direction only
)
JEiWneither direction
2When analyzing projectile motion, the vertical motion can
projectile were ft ‘e 4L
and the horizontal motion can be analyzed as
3. If air resistance is included in analysis of projectile motion, the maximum vertical
height is
than if it were not included.
4. If air resistance is included in analysis of projectile motion, the horizontal range is
I ‘, than if it were not included.
5. A helicopter, with a horizontal velocity of 74 mIs, drops a package that reaches the
ground in 4.6 seconds.
a. How far has the package traveled horizontally?
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b. How far did it fall vertically?
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c. What was its vertical velocity just before it hit the ground?
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6. Mrs. Celin is preparing to fire her potato cannon horizontally off the edge of the roof
of HSN, 15 m high. She thinks the potato will exit the cannon at 37 m/s.
a. What is her prediction for how far away the potato will land?
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b.
What is her prediction for how long it is in the air?
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7. After confidently predicting the horizontal distance and the time in the air, Mrs Celin fires the cannon.
Students, with stopwatches and metersticks in hand, stand below to time the flight and measure the
horizontal distance. The average measured horizontal distance is determined to be 25 m. Time data
was unreliable and none can be used in further calculations.
a. Use the time you calculated in #6 and the measured horizontal distance of 25 m to recalculate the
horizontal velocity of the potato as it left the cannon.
b. Can you explain why the predictions don’t match the measurements?
8. You are a U of Colorado physics major and notice that the ‘projectile motion’ simulation does not
include a choice of ‘W for different planets. You are recruited to write an additional program that gives
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the user a choice of planets. Remember on earth the acceleration due to gravity is 10 rn/s
a. How would you modify the equations that the program uses (and you use in class)
•
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For the moon where the gravity is 1/6 of earth’s?
For Jupiter where the gravity is 2.4 times greater than earth’s?
b. Recalculate # Sb as if you were on Jupiter.
J.
A football is kicked at an angle up into the air. If air resistance is ignored, describe
the acceleration of the football:
a. iti zero at
(t is -10 mIs at all times
c. it is zero at the top of the
(negative is downward)
trajectory at all times
d. it is positive on the way up and negative on the way down
A.
A ball is thrown straight off a cliff with a horizontal velocity of 15 rn/s. THIS IS
REAL LIFE and you must include air resistance.
Right before the ball hits the ground, the horizontal velocity is
c. greater than 15 rn/s
b. zero
a. 15 rn/sec
(ss than 15 rn/s
..4 Ignoring air resistancthhorizontal component of the projectile’s velocity
b. accelerates
a. is constant
Which of the following is NOT an example of projectile motion?
a. a volleyball served over a net
b. a baseball hit by a bat
acannonball shot off a cliff
7 d. an airplane flying flat and level
Each of the diagrams below shows a projectile with different horizontal velocity or
different starting height.
LABEL which projectile(s) hit the ground FIRST.
Some may hit at the same time.
LABEL which projectile(s) hit the ground LAST.
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For numbers Z
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use the following situation.
A cannonball is launched horizontally from a tower of a castle
with a speed of 12 rn/s and at a height of 16 meters,
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Ignore air resistance. Use a -10 m/s
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£ What is the vertical velocity at the exact time of the launch?
b. -12 rn/s
a. 0 rn/s
b. -12 rn/s
d.-2m/s
c. -10 rn/s
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d. -30 rn/s
,,i1. If the cannonball is launched from a higher spot on the castle, the fmal vertical
velocity of the cannonball would be:
a. the same
(heater)
c. less.
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If a bigger cannon with greater speed were used, the horizontal distance traveled
would be:
a. the same
(i.
greater
c. less.
In her physics lab experiment, Wanda rolls a marble down a ramp and off the table.
The marble has a horizontal velocity of 2.1 rn/s as it rolls off and it lands 60 cm from the
edge of the table, How high is the table?
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