2D Energy Efficiency Flashcards
1
Q
what does efficiency measure
A
how much of the energy put into a system is used for useful work
2
Q
energy efficiency formula
A
Efficiency = (Output Energy / Input Energy) × 100%
3
Q
why is no machine or process is 100% efficient
A
because some energy will always escape as heat. this is why engines get hot and why nothing works perfectly forever
4
Q
what happens when energy is transferred / transformed
A
some of it becomes heat due to friction, air resistance or insufficiencies
- less energy is available for useful work
