The working fluid of an ideal heat engine receives 600 J of heat from the heater in one cycle.

The working fluid of an ideal heat engine receives 600 J of heat from the heater in one cycle. 60% of this heat is transferred to the refrigerator. Refrigerator temperature 0 (degrees Celsius) determine the heating temperature.

We translate the units of measurement into the СІ system and write down what is given and what needs to be found:

Qн = 600 J Тх = 273 К Тн-?

Qx = 0.6 * Qн – we find how much heat the refrigerator received.

The efficiency of an ideal heat engine is η = (Qn – Qx) / Qn; also η = (Tn – Tx) / Tn;

(Qн – Qx) / Qн = (Тн – Тx) / Тн;

Tn = Qn * Tx / Qx = 273 / 0.6 = 455 K