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Question
How is the mechanical advantage related with the velocity ratio for an actual machine? State whether the efficiency of such a machine is equal to 1, less than 1 or more than 1.
Solution
The mechanical advantage of an actual machine is equal to the product of its efficiency and velocity ratio.
M.A. = V.R. × η
The efficiency of such a machine is always less than 1, i.e., η < 1. This is because there is always some loss in energy in the form of friction, etc.
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