Energy And Efficiency Flashcards
1
Q
How do you work out the efficiency of an appliance?
A
The efficiency of an appliance =
Useful energy
transferred by the
appliance
Efficiency= ———————————(x100%)
Total energy supplied to
the appliance
2
Q
What is the most efficient a machine can get?
A
No machine can be more than 100% efficient.
3
Q
Measures to make machines more efficient include reducing what?
A
- friction
- air resistance
- electrical resistance
- noise due to vibrations
4
Q
How is energy measured?
A
Energy is measured in joules (J). The unit used for all forms of energy
