Question

calculate the effort applied in the upward direction in case of a single movable pulley which lifts a bucket of water of weight 30kgf if efficiency of the given pulley system is 60%

Answer 1

Answer:

The effort applied in the upward direction in the case of a single moveable pulley with load $30kg$ and efficiency $60$% is $25kg$.

Explanation:

A single movable pulley is a type of pulley, whose axis of rotation is not fixed in position, that is it can freely move.

The mechanical advantage of a pulley is given by the ratio of load to the effort.

$MA=load(L)/effort(E)$

From the question, we have the weight of the load (bucket of water) is $L=30kg$

to calculate the effort =$Load/MA$

It is given that efficiency of the pulley η=$60%$%

The equation for calculating the efficiency is

η=$mechanical advantage /velocity ratio$

To calculate mechanical advantage substitute the given values

MA=$\frac{60(VR)}{100}$

the velocity ratio of a single moveable pulley equals distance traveled by E divided by the distance traveled by L, it's value is $VR=2$

$MA=\frac{60(2)}{100}=6/5$

therefore effort =$\frac{30(5)}{6} =25kg$