Question

A physicist does 100 joules of work on a simple machine that raise a box of bioks through a heigjt of 0.2metres. if the efficiency of the machine is 60%, how much work is converted to thermal energy?​

Answer 1

Answer:

the work converted to thermal energy is 40 J.

Explanation:

Given;

work done by the physicist,w = 100 J

height through which the book is raised, h = 0.2 m

efficiency of machine = 60% = 0.6

The useful work done by the machine is calculated as;

useful work = 0.6 x 100 = 60 J

The wasted energy = 100 J - 60 J

The wasted energy = 40 J

The wasted energy by the machine is possibly converted to thermal energy by the frictional part of the machine.

Therefore, the work converted to thermal energy is 40 J.