Question

An object with a mass of `8 kg` is hanging from an axle with a radius of `18 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 `=88.67J`

Explanation:

The load is `L=8gN`

The radius of the axle is `r=0.18m`

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

The effort is `=FN`

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

Taking moments about the center of the axle

`F*0.45=8g*0.18`

`F=(8g*0.18)/0.45=31.36N`

The force is `F=31.36N`

The distance is `d=2*pi*0.45m`

The work is

`W=Fxxd=31.36*0.90pi=88.67J`