(i) In what way does an 'Ideal machine' differ from a 'Practical machine'?
(ii) Can a single machine act as a force multiplier and a speed multiplier at the same time?
(i) The efficiency of an ideal machine (free from friction etc) is equal to $$1$$. But in actual practical, the efficiency is less than $$1$$ due to the energy loss in friction.
(ii) A single machine cannot act as a force multiplier and a speed multiplier at the same time.