Define the term efficiency of a machine. Give two reasons for a machine not to be 100% efficient?

Define the term efficiency of a machine. Give two reasons for a machine not to be 100% efficient?

Class 10 | ICSE | Machines | Physics | Selina

Define the term efficiency of a machine. Give two reasons for a machine not to be 100% efficient?

Solutions:

The term efficiency of a machine is defined as the ratio of the machine’s work on a load to the work done on the machine by the effort, or efficiency is the ratio of work output to work input.

In practical machines, there is always some energy loss owing to friction and the weight of moving parts. As a result, the output energy is lower than the intake.

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