P1.2 Energy and efficiency Flashcards
1
Q
What does a Sankey diagram do?
A
Shows us the input energy, the output energy and the wasted energy
2
Q
What can’t energy be?
A
Created or destroyed
3
Q
What can energy be?
A
- Transferred usefully form one energy to another
- Stored
- Dissipated
4
Q
How can energy be useful?
A
Only if it can be converted from one energy type to another
5
Q
Give an example of useful energy
A
Solar panels convert thermal energy from the sun to electrical energy
6
Q
What happens when waste energy goes out into its surroundings?
A
It gets warmer
7
Q
What is the equation for efficiency in percentage?
A
Efficiency = Useful energy out / total energy in x 100
Efficiency = Useful power out / total power in x 100
