A-LEVEL PHYSICS: 11.2.8: Engine Efficiency (SaveMyExams) Flashcards
1
Q
the efficiency of an engine can be measured in 3 different ways:
A
-overall
-thermal
-mechanical
2
Q
overall efficiency = …
A
overall efficiency = brake power / input power
3
Q
thermal efficiency = …
A
thermal efficiency = indicated power / input power
4
Q
mechanical efficiency = …
A
mechanical efficiency = brake power / indicated power
5
Q
what does thermal efficiency of an engine tell us
A
how well the engine transforms the chemical energy in fuel into the useful power (and work) in the engine cylinders
6
Q
the mechanical efficiency of an engine depends on…
A
the amount of energy lost due to moving parts of the engine (due to friction)
