Question

If a gasoline engine has an efficiency of 21 percent and losses 780 J to the cooling system and exhaust during each cycle, how much work is done by the engine?

Answer 1

207.3 J

Step-by-step explanation:

Answer 2

As we know that efficiency of engine is given as

`efficiency = (W)/(Q_i)`

also we know that

`Q_i - Q_o = W`

given that

`Q_o = 780 J`

efficiency = 21%

now we have

`0.21 = (Q_i - Q_o)/(Q_i)`

`0.21 Q_i = Q_i - 780`

`0.79Q_i = 780`

`Q_i =987.3J`

now we have

`W = 987.3 - 780 = 207.3 J`