Kinetic Energy
Potential Energy
Energy Flow
Work and Power
Misc.
100
Define kinetic energy.
The energy of motion.
100
Define Gravitational Potential Energy.
Energy Stored in raised objects.
100
A gallon of gas contains 34,000,000 J of stored energy. The energy is transferred to the motion of the car with an efficiency of 24%. How much energy is used to move the car?
8,160,000 J
100
Word depends on ____ exerted on an object and the _____ it is pushed.
Force, distance
100
What type of energy does a does a boiling pot of water contain?
Heat energy or thermal energy
200
A soccer ball with a mass of 0.826 kg is kicked through a goal post at 38 m/s. What is the kinetic energy?
596.37 J
200
A 0.1 kg apple hangs 3 m above the ground. What is the gravitational potential energy of the apple?
2.94 J
200
What is the main energy conversion within a vehicle? (What do you put in and what do you get out?)
Chemical energy to Kinetic energy
200
A 1500 kg car is pushed with a force of 270 N over a distances of 15 m. What is the work done on the car?
6,007,500 J
200
Food and gasoline contain what type of energy?
Chemical energy (sometimes called caloric)
300
After your car broke down, you are forced to push it down the road with a velocity of 1.5 m/s. If the car has 2250 J of kinetic energy, what is the mass of the car?
2000 kg
300
A ball has a potential energy of 100 J on a ledge that is 2 meters high. What is the mass of the ball?
5.1 kg
300
Roller coasters transfer mechanical energy to ___________ to kinetic energy.
Potential energy
300
A 1500 kg car is pushed by a person with a force of 230 N and moves a distance of 21 m. What is the work done by the GROUND?
0 J
300
Define energy?
The ability to do work or the ability to make a change in something.
400
If the velocity of an object is doubled, how does the kinetic energy change?
Quadrupled! (x4)
400
If the height is doubled, the potential energy is _________.
Also doubled!
400
A 1700 kg car parked on a 10 m hill releases its brakes. How fast will the car move when it reaches the bottom of the hill?
14 m/s
400
At the mechanic, your 1700 kg vehicle may need to lifted to see the underside. How much power is required to lift it 1.5 meters over 10 seconds?
2499 W or J/s
400
When doing a pushup, what does the work when lowering back to the floor?
Gravity!
500
One day you accidentally lock yourself in your room. To break out, you (a 70 kg person) need a kinetic energy of 157.5 J. What velocity must you run to make it out?
2.12 m/s
500
An astronaut on a mysterious planet has a mass of 100 kg. The astronauts suit tells her that on top of a 20 m cliff, she has a potential energy of 5600 J. What is the gravitational acceleration on this planet?
2.8 m/s^2
500
A car moving at 15 m/s approaches a hill. What is the height this car will be above the ground when it stops moving?
11.47 m/s
500
When searching for a new car, the sales person tells you this 250 horsepower (186425 W) car with a mass of 1500kg can go from 0 mph to 60 mph (0 m/s to 26.8 m/s) in 2 seconds. Is this true? How long should it take?(Hint: How long must it take to get to this speed with this power? What is the change in energy?)
The sales person is wrong! It should take 2.9 s to get up to speed.
500
What is the law of conservation of energy?
Energy cannot be created or destroyed, only transferred.
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