Vocabulary
Define energy.
The ability to do work.
I am riding my bike down a hill. PE or KE?
Kinetic energy
How does increasing mass change kinetic energy?
When mass increases kinetic energy increases (proportional relationship)
What is the potential energy of a 60 kg object sitting on a 17 meter shelf in a store room.
PE=9,996 J
What is the mechanical energy (aka total energy) of a roller coaster at 40 m with KE of 116,200 J and PE 26,800 J?
ME=143,000 J
Define gravitational potential energy.
Gravitational potential energy
How does doubling the velocity change kinetic energy?
Kinetic energy will quadruple!
W=3,841 J
If the total energy in a system is 195,000 J and GPE is 33,700 J how much kinetic energy is there?
KE=161,300 J
What does the Law of Conservation of Energy state?
Energy cannot be created nor destroyed, only transformed.
A sling shot being pulled back. PE or KE?
Elastic potential energy
How is PE transformed into KE while riding a sled down a snowy hill.
What is the kinetic energy of a 56 kg object that is traveling at a velocity of 22 m/s?
What is the mass of an object with 158,000 J of PE and is sitting 84 m from sea level?
m=191.93 kg
What is mechanical energy?
The combination of kinetic and potential energy in a system.
A bowling ball rolling down the lane. PE or KE?
Kinetic energy
What is the difference between elastic potential energy and gravitational potential energy.
GPE: stored energy as a result of height
EPE: stored energy as a result of object being stretched/compressed
How much power is developed when moving a 60 kg object 22 meters with a force of 198 N for 3 minutes?
P=24.2 W
What is the mass of an object traveling 34m/s with 124,300 J of KE?
m=215.05 kg
What is elastic potential energy?
Stored energy as a result of an object being stretched or compressed.
Biking up a hill. PE or KE?
How is the available mechanical energy reduced during a roller coaster ride?
The wheels on the track generate friction which creates thermal energy. This thermal energy drains the available mechanical energy, reducing it ultimately slowing the cart down.
What is the velocity of a 68 kg object that has 120,000 J of KE?
v=59.41 m/s
How could you calculate the power exerted by someone climbing the stairs?
By the work exerted in the time it took to walk up the stairs.
OR
By the force exerted times the distance traveled in the time it took to walk up the stairs.