Work
KE
PE
Cons. of Energy
Power
100
In order for work to be done, what must be true of force and displacement
they must be parrallel
100
if an object is not moving it has _____ KE
0
100
Potential energy is the energy due to ____
position
100
When is mechanical energy conserved?
when there is no friction
100
The unit for powe is called the
Watt. Know the other forms.
200
If the sign of work is positive, this means that .....
force and displacement are in opposite directions. Example: friction
200
The sign of kinetic enrgy is ______ positive
always
200
The work done lifting an object is _____ its change in potential energy
equal to
200

The __________________  is conserved as a racecar driver makes one rotation on a loop de loop.

What is the total energy?

200
If a job done two different ways requires the same amount of work, how is power affected
depends on the time
300
a car slows down on a flat road. is work being done
yes
300
Ball A has double the mass of ball B. What is the ration of KE of A to B
2:1
300

The potential energy of a hiker on top of a 50km hill ________________ as he approaches the ground

What is a decrease in potential energy?

300
Friction converts kinetic energy to ___
Heat
300
The distance an object is pushed doubles while the time it takes to do the work is cut in half, what happens to the power
4 times greater
400
What is the units of Work
Joules, N*m or Kgm^2/s^2
400
If the velocity of an object triples its KE will be
nine times greater
400
Potential energy is always measured relative to _____
an arbitrary zero level
400

if friction is negligible, what will be the kinetic energy of an arrow that is shot out of a bow that has a potential energy of 70 J

70 J

400
If the power an object has triples what will happen to its speed
it will triple
500

If speed is constant during the motion, will it affect how much work is done

no

500

If friction is the only force acting on an object its KE will?

decrease

500

if the length of a stretched spring is is cut in half, its elastic potenital energy would be _________

1/4

500
Energy is changed from one form to another with no net loss or gain is ________ (T or F)
Always true
500
The kilowatt-hour is a measure of _____
Energy
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