Question 534: Thermodynamics & KTG

Question

A Carnot engine, having an efficiency of $$\eta  = 1/10$$ as heat engine, is used as a refrigerator . If the work done on the system is $$10$$ $$J$$, the amount of energy absorbed from the reservoir at lower temperature is

Accepted Answer

The efficiency $$\left( \eta  ight)$$ of a Carnot engine and the coefficient of performance $$\left( \beta  ight)$$ of a refrigerator are related as
$$\beta  = {{1 - \eta } \over \eta }$$
$$\,\,\,\,\,\,$$ Here, $$\eta  = {1 \over {10}}$$
$$\,\,\,\,\,\,$$ $$	herefore$$ $$\beta  = {{1 - {1 \over {10}}} \over {\left( {{1 \over {10}}} ight)}} = 9.$$
Also, Coefficient of performance $$\left( \beta  ight)$$ is given by $$\beta  = {{{Q_2}} \over W},$$
where $${Q_2}$$ is the energy absorbed from the reservoir.
or, $$9 = {{{Q_2}} \over {10}}$$
$$	herefore$$ $${Q_2} = 90\,J.$$

Answer

$$100$$ $$J$$

Answer

$$99$$ $$J$$

Answer

$$90$$ $$J$$

Answer

$$1$$ $$J$$

Thermodynamics & KTG

A Carnot engine, having an efficiency of $\eta = 1/10 as heat engine, is used as a refrigerator . If the work done on the system is 10 J$, the amount of energy absorbed from the reservoir at lower temperature is

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