A heat engine absorbs 126 kcal of heat and exhausts 77 kcal of heat in each cycle. Calculate the efficiency (as a percentage)
eff = [(126-77)/126]*100 = ?
I got 38.88 is that correct?
I obtained 38.8889 so I would round that to 38.9 but I believe you're allowed only 2 s.f.
so basically 39%?
To calculate the efficiency of a heat engine, you need to use the formula:
Efficiency = (Useful output energy / Input energy) x 100
In this case, the useful output energy is given as the heat exhausted, which is 77 kcal. The input energy is given as the heat absorbed, which is 126 kcal.
Substituting these values into the formula:
Efficiency = (77 kcal / 126 kcal) x 100
Efficiency = 0.6111 x 100
Efficiency = 61.11%
Therefore, the efficiency of the heat engine is 61.11%.