Question

A woman draws water from a well using a fixed pulley. The mass of the bucket and water together is $6.0\mathrm{kg}$. The force applied by the woman is $70\mathrm{N}$. Calculate the mechanical advantage. (Take $g=10\mathrm{m}/{\mathrm{s}}^2$ )

Answer 1

Step 1: Given data:

The force applied by the woman is $\mathrm{E}=70\mathrm{N}$

The mass of the bucket and water together is $m=6kg$

The acceleration due to gravity is $g=10\mathrm{m}/{\mathrm{s}}^2$

Step 2: Calculate the load,

Load in the given case is equivalent to the weight of the system, thus,

Load using force $=$ Weight as,

$$\begin{gathered} \mathrm{L}=\mathrm{mg} \\ =6\times 10 \\ =60\mathrm{N} \end{gathered}$$

Step 3: Find the mechanical advantage,

The mechanical advantage in terms of load and effort is,

$$\begin{gathered} \mathrm{MA}=\frac{\mathrm{Load}\left(L\right)}{\mathrm{Effort}\left(E\right)} \\ \mathrm{MA}=\frac{60}{70} \\ \mathrm{MA}=\frac{6}{7} \\ \mathrm{MA}=0.857 \end{gathered}$$

Thus, the mechanical advantage in the given case is $0.857$.