Question

An object with a mass of `5 kg` is hanging from an axle with a radius of `21 cm`. If the wheel attached to the axle has a radius of `14 cm`, how much work would it take to turn the wheel `7 cm`?

Answer 1

The work is `=5.145J`

Explanation:

The load is `L=5gN`

The radius of the axle is `r=0.21m`

The radius of the wheel is `R=0.14m`

The effort is `=FN`

The acceleration due to gravity is `g=9.8ms^-2`

Taking moments about the center of the axle

`F*0.14=5g*0.21`

`F=(5g*0.21)/0.14=73.5N`

The force is `F=73.5N`

The distance is `d=0.07m`

The work is `W=Fxxd`

`W=73.5*0.07=5.145J`