P1.2 Energy and Efficiency Flashcards
1
Q
State the 9 forms of energy.
A
Energy can’t be made or destroyed.
Only be transferred to and from the following;
Sound, light, heat, electrical, kinetic, elastic, chemical, gravitational, and nuclear.
2
Q
What is the unit for energy?
A
Normally measured in Joules - J.
3
Q
What form is energy normally in when it is wasted?
A
When energy is transferred some of it is always wastes usually as heat or sound.
4
Q
Why is wasted energy difficult to use again?
A
When energy is wasted it eventually heats up the surroundings becoming spread out.
5
Q
Define efficiency.
A
How well an object transfers input energy into useful energy.
6
Q
What is the equation cost effectiveness (payback time)?
A
Cost effectiveness = initial cost divided by yearly saving.
