Lakhmir Singh and Manjit Kaur Solutions for Chapter: Work and Energy, Exercise 19: Multiple Choice Questions (MCQs)

Which of the following energy change involves frictional force?

Which one of the following statements about power stations is not true?

An electric motor raises a load of $0.2 \mathrm{kg}$, at a constant speed, through a vertical distance of $3.0 \mathrm{m}$ in $2 \mathrm{s}$. If the acceleration of free fall is $10 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{${\mathrm{s}}^2$}\right.$, the power in $\mathrm{W}$ developed by the motor in raising the load is:

An object is falling freely from a height $\mathrm{x}$. After it has fallen a height $\frac{\mathrm{x}}{2}$ , it will possess:

The commercial unit of energy is:

How much energy does a $100 \mathrm{W}$ electric bulb transfer in $1$ minute?

The device which converts mechanical energy into energy which runs our microwave oven is:

A microphone converts: