Question

An object with a mass of `5 kg` is hanging from an axle with a radius of `12 cm`. If the wheel attached to the axle has a radius of `45 cm`, how much work would it take to turn the wheel a length equal to the circumference of the axle?

Answer 1

The work is `=36.9J`

Explanation:

The load is `L=(5g)N`

The radius of the axle is `r=0.12m`

The radius of the wheel is `R=0.45m`

The effort is `=(F)N`

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

Taking moments about the center of the axle

`F*0.45=5g*0.12`

`F=5g*0.12/0.45=13.1N`

The force is `F=13.1N`

The distance is `d=2piR=2pixx0.45=(0.9pi)m`

The work is

`W=Fxxd=13.1*0.9pi=36.9J`