Heat Engines — Prelims Questions

A heat engine absorbs $600\,\text{J}$ of heat from a source at $400\,\text{K}$ and rejects $200\,\text{J}$ of heat to a sink at $300\,\text{K}$. What is the efficiency of the engine?

A Carnot engine operates between $227^\circ\text{C}$ and $27^\circ\text{C}$. What is its efficiency?

A heat engine performs $100\,\text{J}$ of work per cycle and has an efficiency of $25\%$. How much heat is rejected to the cold reservoir per cycle?

Which of the following statements about a heat engine is FALSE?

A Carnot engine takes $1000\,\text{J}$ of heat from a reservoir at $500\,\text{K}$ and rejects heat to a reservoir at $300\,\text{K}$. What is the work done by the engine?

An engine has an efficiency of $30\%$. If it absorbs $1500\,\text{J}$ of heat from the source in each cycle, how much heat does it reject to the sink?