Question

A block and tackle system has 5 pulleys. Effort of 1000 N required in down ward direction to raise a load of 45000N. Calculate MA, VR and n of the system with drawing diagram.​

Answer 1

Given:

Pulleys = 5

Effort = 1000N

Load = 4500N

To find:

The Mechanical Advantage

The Velocity Ratio, and

The Efficiency of the System.

Solution:

The Mechanical Advantage:

Mechanical Advantage = Load / Effort

Mechanical Advantage = 4500 / 1000

Mechanical Advantage = 4.5

The Velocity Ratio:

Velocity Ratio = Number of strings supporting the Load

Velocity Ratio = 5

The Efficiency of the System:

Efficiency = MA / VR

Efficiency = 4.5/5

Efficiency = 90%