Question

An engine wastes 491 J of heat while producing 670 J of work. How much heat must be coming into the engine from a hot reservoir?

Answer 1

1161 J

Explanation:

As the body wastes 491 J,i.e,rejects that amount of heat to the cold reservoir(`Q_2`) and performs 670 J of work(`W`),then the total amount of heat absorbed by the body from the hot reservoir(`Q_1`) would be,
`Q_1=W +Q_2`
Thus `Q_1`=670+491 OR 1161 J