Question

mechanical advantage is defined as

• A. $\frac{\mathrm{load}\mathrm{arm}}{\mathrm{effort}\mathrm{arm}}$
• B. $\frac{\mathrm{effort}\mathrm{arm}}{\mathrm{load}\mathrm{arm}}$
• C. $\mathrm{load}\times \mathrm{load}\mathrm{arm}$
• D. $\mathrm{effort}\times \mathrm{load}\mathrm{arm}$

Answer 1

The correct option is B

$\frac{\mathrm{effort}\mathrm{arm}}{\mathrm{load}\mathrm{arm}}$

1. The amplification of force that a machine helps us achieve is called mechanical advantage.
2. Mechanical advantage is defined as the ratio of $\frac{\mathrm{Load}\left(\mathrm{L}\right)}{\mathrm{effort}\left(\mathrm{E}\right)}$
3. The work is done same on two sides or two arms
   $$\begin{gathered} \Rightarrow \mathrm{Load}\times \mathrm{distance}\mathrm{moved}\mathrm{by}\mathrm{the}\mathrm{load}\mathrm{arm}=\mathrm{effort}\times \mathrm{distance}\mathrm{moved}\mathrm{by}\mathrm{the}\mathrm{effort}\mathrm{arm}---\left(1\right) \\ \mathrm{or}\mathrm{load}\times \mathrm{load}\mathrm{arm}=\mathrm{effort}\times \mathrm{effort}\mathrm{arm}---\left(2\right) \\ \Rightarrow \mathrm{Thus}\mathrm{from}\left(1\right)\mathrm{and}\left(2\right)\mathrm{we}\mathrm{say}\mathrm{that}\mathrm{load}\mathrm{mechanical}\mathrm{advantage}=\frac{\mathrm{Load}\left(\mathrm{L}\right)}{\mathrm{effort}\left(\mathrm{E}\right)}={\frac{\mathrm{effort}\mathrm{arm}}{\mathrm{load}\mathrm{arm}}}_{} \end{gathered}$$
   Hence option (b) is the correct answer.