Q. 7

Expert-verified
Found in: Page 594

### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

Book edition 4th
Author(s) Randall D. Knight
Pages 1240 pages
ISBN 9780133942651

# The power output of a car engine running at is . How much (a) work is done and (b) heat is exhausted per cycle if the engine's thermal efficiency is ? Give your answers in .

(a) Work done per cycle

(b)Heat exhausted per cycle

See the step by step solution

## Step 1:Definition of thermal efficiency (part a)

The fraction of heat, , converted to work W is denoted by the thermal efficiency, . It is expressed as follows.

The energy input is split between the mechanical energy required to move the car and the heat released into the environment:

2400 rpm per second.

And work per cycle is

## Step 2:Explanation (part b)

Thermal efficiency iis the proportion of work gained to energy invested.

As a result, the total energy input per cycle must be

The heat lost during one cycle is equal to the difference between the energy input and the work done: