Question

An object with a mass of `8 kg` is hanging from an axle with a radius of `5 cm`. If the wheel attached to the axle has a radius of `25 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 `=24.6J`

Explanation:

The load is `L=8gN`

The radius of the axle is `r=0.05m`

The radius of the wheel is `R=0.25m`

The effort is `=FN`

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

Taking moments about the center of the axle

`F*0.25=8g*0.05`

`F=8g*0.05/0.25=15.68N`

The force is `F=15.68N`

The distance is `d=2piR=2*pi*0.25=(0.5pi)m`

The work is `W=Fd=15.68*0.5pi=24.6J`