An object with a mass of #7 kg# is hanging from an axle with a radius of #25 cm#. If the wheel attached to the axle has a radius of #75 cm#, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Mar 29, 2017

The work done is #=35.92J#

Explanation:

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The load #=(7g)N#

Radius of axle #r=0.25m#

Radius of wheel #R=0.75m#

Taking moments about the center of the axle

#F*0.75=7*g*0.25#

#F=(7*g*0.25)/0.75=7/3g=22.87N#

The distance is #=2*pi*0.25=0.5pi#

The work done is

#W=F*d=22.87*0.5pi=35.92J#