What is the efficiency of a heat engine? Write its formula.
(N/A) The efficiency $\eta$ of a heat engine is defined as the ratio of the net work done $(W)$ by the engine per cycle to the total heat absorbed $(Q_H)$ from the hot reservoir (source) per cycle.
It represents the fraction of heat energy converted into useful work.
The formula for efficiency is given by:
$\eta = \frac{W}{Q_H}$
Since $W = Q_H - Q_L$ (where $Q_L$ is the heat rejected to the cold reservoir or sink), the formula can also be expressed as:
$\eta = 1 - \frac{Q_L}{Q_H}$
Efficiency is typically expressed as a percentage by multiplying the result by $100\%$.
It represents the fraction of heat energy converted into useful work.
The formula for efficiency is given by:
$\eta = \frac{W}{Q_H}$
Since $W = Q_H - Q_L$ (where $Q_L$ is the heat rejected to the cold reservoir or sink), the formula can also be expressed as:
$\eta = 1 - \frac{Q_L}{Q_H}$
Efficiency is typically expressed as a percentage by multiplying the result by $100\%$.
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View Solution$Assertion :$ The Carnot cycle is useful in understanding the performance of heat engines.
$Reason :$ The Carnot cycle provides a way of determining the maximum possible efficiency achievable with reservoirs of given temperatures.
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