Work
True or False: Work is a scalar quantity
True
Kinetic Energy is the energy of _____
motion
Gravitational Potential Energy is the energy of an object due to its….
Height/ position
Power is......
amount of work done in a given amount of time
P = W/t
What unit is used for work?
Joule
If the velocity of an object gets doubled, its kinetic energy will be increased by a factor of what?
4/ quadrupled
What type of potential energy does each of the following items have:
a) a compressed spring
b) a rock sitting on top of a ledge
a) elastic potential energy
b) gravitational potential energy
What is your power when you do 100 J of work on an object in 2.0 seconds?
50 Watts
The fourth floor of a house is 12.0m above street level. If a force of 1127N is applied to a refrigerator to move it, how much work must be done to move it to the fourth floor of the house?
13, 524 J
A 10 kg object move 3 m/s. It’s kinetic energy is…
45 J
What does k and x stand for in the elastic potential energy equation?
k = spring constant
x = distance stretched or compressed
A horse does 50,000J of work in 20 seconds while a small go kart does 1,000J of work in 1 second. Which one has exerted more power?
The horse, horse's power = 2,500W here, go kart's = 1,000W
A block of wood is pushed at a constant velocity with a force of 25.0 N. How far did it travel if 100.0 J of work are done on it?
4 m
What is the mass of an object that has 1536 J of kinetic energy and is moving at 16 m/s?
12 kg
How much potential energy does a 12.0 kg bowling ball have if it is sitting 0.5 m above the ground?
58.86 J
If your power is 5 Watts, and you do 50 J of work on the object, how long (for how much time) have you been doing work on the object?
10 seconds
How much work is done when you lift a 6.0 kg mass 1.5 m above the ground?
F = (6 kg) (9.8 m/s2) = 58.8 N
W= F x D = (58.8 N) (1.5m)
W= 88.2 J
A 5kg ball is thrown so that it has a kinetic energy of 250J. What is the ball’s speed?
v= 10 m/s
How far off the ground is a 23 kg crate if it has a gravitational potential energy of 5640.75 J?
25 m
If an 203.87 kg object experiences a force for 20 meters and 1/2 second, what is the power?
79998.59 Watts