Question

Figure shows a block and tackle system of pulleys used to lift a load. When load is pulled up by a distance 1 m, how far does the effort end move?

Answer 1

Given:
The block and tackle system consists of 4
pulleys, i.e. $n=4$
Velocity ratio of block and tackle system of n
pulleys is
$V.R.=\frac{d_E}{d_L}=n$
$\Rightarrow d_E=n{d}_L$
In a system of $n=4$ pulleys, if the load moves
up through a distance d, each segment of
string supporting the load gets loosened by a
length d.
So if $d_L=1m$ then distance moved by the
effort end is $d_E=n{d}_L=4\left(1m\right)=4m$