Question

A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 5.90×10−2 kg . Throughout this problem use Lf=3.34×105J/kg for the heat of fusion for water. Part A During this time, how much work W is performed by the engin

Answer 1

W = 7.214 k J

Step-by-step explanation:

given,

time of operation = 5 minutes

mass of ice melt = 5.90 × 10⁻² kg

L_f = 3.34 × 10⁵ J/kg

Work done = ?

We know work done

`|W| = |Q_h| - |Q_c|`

`Q_c = - m L_f`

`Q_c= - 5.90* 10^(-2)* 3.34 * 10^5`

`Q_c = -19.706 kJ`

`Q_h = Q_c (T_H)/(T_C)`

T_H is the heat from hot reservoir = 373 K

T_C is the energy released to cold reservoir = 273 K

`Q_h = -19.706* (373)/(273)`

`Q_h =-26.92 kJ`

now,

`|W| = |-26.92| - |-19.706|`

W = 7.214 k J