Work
W = FΔx
What does ME stand for and what does it mean?
Mechanical energy, total energy
What is the equation for power with work in it?
P = W/t
What is the equation for mechanical energy?
ME = GPE + KE
convert the mass into weight using the equation w = mg
What is the law of conservation of energy?
energy cannot be created or destroyed; or total mechanical energy is conserved in a system
The unit for power is.....
Watts
When a pendulum swings, DRAW where the pendulum has the MOST kinetic energy? At this points is there any potential energy? yes or no.
See drawing. Should be at the center.
Steve does 2000 J of work over 20 m. How much force did he apply during that 20 m?
100 N
There are two kinds of potential energy. What are their abbreviations and what do they stand for?
GPE (gravitational potential energy); EPE (elastic potential energy)
If P = FV, and Julia runs at 2 m/s to produce 150 W. How much force did she produce?
75N
ME = GPE + KE
Frances uses 20 W of power while driving for 30 s. How much work did the car do?
600 J
Joey's refrigerator is more energy efficient than Frank's. What does this mean about Frank's refrigerator?
Frank's refrigerator looses more energy due to heat, sound, and friction.
Sarah does 1200 J of work for 1 minute. How much power does she produce?
20 W of power
A roller coaster sits at the top of a hill not in motion. What is the equation for its mechanical energy?
ME = GPE
Teagan produces 2000 J of work after running for 20 minutes. How far did she run, if she pulls with 20 N of force?
100 m
As a roller coaster goes up a hill the ___________ decreases and the _____________ increases.
Kinetic energy; gravitational potential energy
14 N
A roller coaster sits at the top of tall drop and then goes through a loop de loop to be level with the ground. At which point on the track is there the most energy in the system?
The energy is the same at every point in the system