Question

The given figure shows a simple lever.

1. What class of lever this figure belongs to?
2. What is the minimum effort to overcome the load of 100 N?
3. What is the mechanical advantage of lever if efficiency of the lever is 100%?
4. What is its velocity ratio?

Answer 1

Given from the Figure:

Load (L) = 100 N

Load Arm (distance from Load to Fulcrum) = 1 m

Effort Arm (distance from Effort to Fulcrum) = 2 m

(i) The Fulcrum is located in the middle (between the Load and the Effort), it is a Class I Lever.

(ii) According to the principle of moments:

Load (L) × Load Arm = Effort (E) × Effort Arm

100 × 1 = E × 2

E = `100/2`

E = 50 N

(iii) Mechanical Advantage (MA) = `"Effort Arm"/"Load Arm"`

= `2/1`

= 2

(iv) For any lever, the velocity ratio depends only on its structure and arms lengths:

Velocity Ratio (VR) = `"Effort Arm"/"Load Arm"`

= `2/1`

= 2