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Question
- State the relationship between mechanical advantage, velocity ratio and efficiency.
- Name the term that will not change for a machine of a given design.
Solution
Relation between M.A., V.R. and η
i. Efficiency = `"Work output"/"Work input"`
= `(L xx d_L)/(E xx d_E)`
= `(L/E)/((dE)/(dL))`
But `L/E` = M.A. and `(dE)/(dL)` = V.R.
Efficiency = η = `(M.A)/ (V.R.)` or M.A. = η × V.R.
ii. For a machine of a certain design, the term velocity ratio remains constant since M.A. = V.R.
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