Question

A pulley system has a velocity ratio 3. Draw a diagram showing the point of application and direction of load (L), effort (E) and tension (T).

It lifts a load of 150 N by an effort of 60 N.

Calculate its mechanical advantage.

Is the pulley system ideal? Give reason.

Answer 1

1. Above is a diagram of the block and tackle pulley system with a velocity ratio of 3, along with markers for the directions of load (L), effort (E), and tension (T).

2. Given L = 150 N, E = 60 N
   Mechanical advantage M.A.
   = `"Load"/"Effort"`
   = `150/60`
   = 2.5
3. This is not the ideal pulley system. For an ideal case the M.A. should be equal n, where n is the number of pulleys of the pulley system. In this case as the mechanical advantage is less than 3 ( i.e. the number of pulleys ) so the pulley system is not ideal.