An object with a mass of #4 kg# is hanging from an axle with a radius of #15 cm#. If the wheel attached to the axle has a radius of #21 cm#, how much work would it take to turn the wheel #9 cm#?

1 Answer
Apr 15, 2017

The work done is #=2.52J#

Explanation:

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The load #=(4g)N#

Radius of axle #r=0.15m#

Radius of wheel #R=0.21m#

Taking moments about the center of the axle

#F*0.21=4*g*0.15#

#F=(4*g*0.15)/0.21=28N#

The distance is

#d=0.09m#

The work done is

#W=F*d=28*0.09=2.52J#