Question

Define efficiency

Answer 1

Step1: For the ideal machine

1. The efficiency of the machine can be defined as the ratio of work output to work input.
2. An ideal machine is that in which there is no loss of energy in any manner.
3. The work output is equal to the work input.
   $\mathrm{Work}\mathrm{output}=\mathrm{work}\mathrm{input}$
4. The efficiency of an ideal machine is 100%.
   $\mathrm{Efficiency}=\frac{\mathrm{work}\mathrm{output}}{\mathrm{work}\mathrm{input}}=100\%$

Step2: For actual machine

1. In an actual machine, the output energy is always less than the input energy, indicating some energy loss during its operation. $\mathrm{Output}\mathrm{energy}<\mathrm{input}\mathrm{energy}$
2. The loss of energy occurs mainly due to - The moving parts in it are neither weightless nor smooth (or frictionless),
3. The string in it (if any) is not perfectly elastic. Its different parts are not perfectly rigid.