Question

A pulley system has a velocity ratio 3 and an efficiency of $80\%$. Draw a labelled diagram of this pulley system. Calculate :

(a) the mechanical advantage of the system, and

(b) the effort required to raise a load of 300 N.

Answer 1

As the velocity ratio is 3, there should be three pulley. now the work efficiency =0.8






V. R.=3 , n=80% , load=300N

(i)
M. A. = V. R. *n%
=3*80/100
=2.4
(ii)
M. A. = load / Effort
Effort = load / M. A.
= 300/2.4
125N