An inventor claims to have developed an engine that during a certain time interval takes in 110 MJ of heat at 415 K, rejects 50 MJ of heat at 212 K while manages to do 16.7 kW of work. Do you agree with the inventors's claim?

An inventor claims to have developed an engine working between 600k and 300k of having an efficiency of 52% . Comment on his claims .

A Carnot engine receives 2.0 kj of heat from a reservoir at 500 K, does some work, and rejects some heat to a reservoir at 350 K. How much work does it do?

Heat flows from a reservoir at 373 K to a reservoir at 273 K through a copper rod as shown in the figure. The heat then leaves the 273 K reservoir and enters a Carnot engine, which uses part of this heat to do work and rejects the remainder to a third reservoir at 173 K . What fraction of the heat leaving the 373 K reservoir is rendered unavilable for doing work, as compared to the situation where a Carnot engine is connected directly between the 373 K and 173 K reservoirs ? ltbr.

Heat flows from a reservoir at 373 K to a reservoir at 273 K through a copper rod as shown in the figure. The heat then leaves the 273 K reservoir and enters a Carnot engine, which uses part of this heat to do work and rejects the remainder to a third reservoir at 173 K . What fraction of the heat leaving the 373 K reservoir is rendered unavilable for doing work, as compared to the situation where a Carnot engine is connected directly between the 373 K and 173 K reservoirs ? ltbr.

A refrigerator is a device used for cooling things. Working substance would absorb a certain quantity of heat Q_(2) from the sink at lower temperature T_(2) and reject a larger amount of heat Q_(1) to the source (surrounding air) at higher temperature T_(1) (= room temperature) with the help of an external agency supplying energy W to the system. Clearly, w=Q_(1)-Q_(2) Cofficient of performance of refrigerator, beta(T_(2))/(T_(1)-T_(2)) = (1-eta)/(eta) Read the above passage and answer the following questions: (i) What is the cofficient of performance of a refrigerator working between -10^(@)C and 25^(@)C ? (ii) 'Refrigerator is an efficient room heater'. Do you agree with the statement? Justify.