Question

A spade of length 1 m is held by a person at a distance of 20 cm from the fulcrum. Calculate.

1. Velocity ratio of the spade.
2. Force required to lift a load of 40 N.

Answer 1

Given: Load arm = 1 m = 100 cm

Effort arm = 20 cm

Load (L) = 40 N

a. Velocity ratio (VR) = `"Effort arm"/"load arm"`

= `20/100`

= 0.2

b. Use the principle of moments:

Load × load arm = Effort × effort arm

40 × 100 = E × 20

E = `(40 xx 100)/20`

= 200 N