5(b)
From the diagram given below, answer the questions that follow:
(i) What kind of pulleys are A and B?
(ii) State the purpose of pulley B.
(iii) What effort has to be applied at C to just raise the load L = 20 kgf?
(Neglect the weight of pulley A and friction).
Show SolutionHide Solution↓
(i) A is a movable pulley and B is a fixed pulley.
(ii) The purpose of pulley B is to change the direction of effort (i.e., in downward direction).
(iii) Given, Load = 20 kgf , M.A. = 2
From relation,
$\text{M.A.} = \frac{\text{L}}{\text{E}}$
Substituting the values in the formula above we get,
$$\begin{aligned}2 = \frac{20}{\text{E}} \\[0.5em] \Rightarrow \text{E} = \frac{20}{2} \\[0.5em] \Rightarrow \text{E} = 10 \text{ kgf}\end{aligned}$$