Question

Q)what do you understand by an ideal machine?how does it differ from a practial machine?​

Answer 1

Answer:

A simple machine, such as a lever, pulley, or gear train, is "ideal" if the power input is equal to the power output of the device, which means there are no losses. ... In this case, the mechanical efficiency is 100%.

Practical machine is a simple machine which losses energy and have parts which have weights, friction and it causes some loss of work done. Practical machine are those which have losses and thats why they do not have 100% efficiency.

Answer 2

Ideal machines are said to have parts which are weightless , frictionless and strings if any are inextensible. Practical machines have parts which have weights, friction and it causes some loss of work done.