Question

An object with a mass of `7 kg` is hanging from an axle with a radius of `8 cm`. If the wheel attached to the axle has a radius of `56 cm`, how much work would it take to turn the wheel a length equal to the circumference of the axle?

Answer 1

34.496J

Explanation:

The mass of the object lifted = `(m)=7kg`

The radius of the axle `(r)=8cm=0.08m`

The radius of the Wheel attached with the axle

`R=56cm=0.56m`

We are to find out the work done to turn the wheel a length

equal to the circumference of the axle. When turning of axle

equal to its circumference`(2pir)` occurs ,the weight is lifted

to the same height`(h= "circumference of axle")` against the gravity .

Hence the work done `W=mgh=mxxgxx2pir=7xx9.8xx2xx22/7xx0.08=34.496J`