Kinematics in 1D
A ball rolls to the right 5 meters, back to the left 7 meters, then right 2 meters.
What is the ball's displacement?
What is 0m?
True or false: the vertical component of a projectiles motion depends on the horizontal component.
What is False?
The gravitational constant is...
What is 6.67x10-11?
Name two different forms of the formula for power.
What is P=w/t, P=Fd/t, mgh/t?
Kinetic and potential energy at the beginning of motion is (>, =, or <) the kinetic and potential energy at the end of motion/
What is equal to?
Determine the velocity of an object that moves 360 m south in 6 seconds.
What is 60 m/s South?
V=d/t
v=360/6
v=60 m/s
A soccer ball is kicked horizontally off a 22.0-meter high hill and lands a distance of 35.0 meters from the edge of the hill. Determine the initial horizontal velocity of the soccer ball.
What is 16.5 m/s?
dy=viyt+1/2at2
22=0t+1/2(9.8)t2
t=2.119
V=d/t
v=35/2.119
v=16.5
Two satellites in space, each with a mass of 2000kg, are 1500m apart from each other. What is the force of gravity between them?
G=6.67∗10−11m3/kg⋅s2
What is 1.19x10−10N?
F=(6.67∗10−11m3kg⋅s2)((2000kg)(2000kg)/(1500m)2)
F=1.19x10−10N
A 50kg man pushes against a wall with a force of 100N for 10 seconds. How much work does the man accomplish?
What is 0 J?
The wall doesn't move,
W=fd
W=100 (0)
W=0
What is the potential energy of a 5kg object that is 35 m above the ground?
What is 1715 J?
PE=5 (9.8) 35
PE=1715
Imagine a decending elevator that is increasing it's speed. What is the direction of the acceleration of the elevator?
If you launch a ball horizontally, moving at a speed of 2.00 m/s from a table that is 1.5 m tall, how far from the base would it land?
What is 1.1 m?
There are two isolated stars orbiting each other. The first star has a mass of 2×1012kg and the second star has a mass of 4.5×1014kg. If the stars are 2,000km away, what is the gravitational force felt by the first star?
G=6.67×10−11m3/kg⋅s
What is 1.5x104 N?
F=6.67x10−11(2x1012kg)⋅(4.5x1014kg)/(2x106m)2
F=1.50x104N
Find the work for this scenario: An upward force is applied to lift a 20kg bag a to a height of 5m. The bag is lifted at a constant speed.
What is 980 J?
W=20 (9.8) 5
W= 980
What is the mass of an object with a kinetic energy of 27 J moving 3 m/s?
What is 6 kg?
KE=1/2mv2
27=1/2m 32
m=6
A 55kg woman has a jet pack that has a mass of 5kg. She ignites the jet pack and it accelerates her at a rate of 5m/s2. Determine the time it took to reach a height of 15m.
What is 2.44s?
d=vit+1/2at2
15=0t+1/2(5)t2
t=2.44
A stone is kicked 8.0 m/s horizontally from a cliff 80 m high. How far from the base of the cliff will the stone strike the ground?
What is 32m?
Two satellites in space, each with a mass of 1723kg, are 890m apart from each other. What is the force of gravity between them?
G=6.67∗10−11m3kg⋅s2
What is 2.5∗10−10N?
F=(6.67∗10−11)((1723kg)(1723kg)/(890m)2)
F=2.5∗10−10N
A weightlifter doing a bench press lifts a 102 kg weight from the base of his chest to a height that is 0.7 m above his chest. How much work has he done after a single lift?
What is 700 J?
W=102 (9.8) .7
W=699.72
Find the velocity of an object that has a mass of 5.4 kg and 72 J of energy?
What is 5.16 m/s?
KE=1/2mv2
72=1/2(5.4)v2
v=5.16
A feather is released from rest on a moon with no atmosphere. The object drops 8.0m in the first second.
What is the magnitude of the acceleration due to gravity on this moon?
What is 16 m/s2?
d=vit+1/2at2
8=0(1)+1/2a(12)
8=1/2a
a=16
A pelican flying horizontally drops a fish from a height of 8.1 m. The fish travels 9.3 m horizontally before it hits the ground. What was the pelican’s speed?
What is 7.32 m/s?
A 2500kg satellite orbits 3.8∗108m above the Earth. What is the acceleration of the satellite?
mass of earth=5.97∗1024kg
G=6.67∗10−11m3/kg∗s
What is
F=(6.67∗10−11)∗(2500)(5.97∗1024)/(6.37∗105m+3.8∗108)2
F=6.87N
F=ma
6.87=2500a
a=.0027
Fido, a small dog that weighs 100N, sees a bird in a tree and climbs straight up, at constant velocity, with an average power of 640.W. If it takes Fido 8.50sec to reach the branch upon which the bird is perched, how high is that branch?
What is 54.4m high?
P= Fd/t
640=100d/8.5
d=54.4
Kinetic energy is the energy _________
and Potential Energy is the energy __________.
What is Of Motion and Stored?