An object with a mass of 3 kg3kg is hanging from an axle with a radius of 3 cm3cm. If the wheel attached to the axle has a radius of 44 cm44cm, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Dec 6, 2017

The work is =5.54J=5.54J

Explanation:

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The load is L=3gNL=3gN

The radius of the axle is r=0.03mr=0.03m

The radius of the wheel is R=0.44mR=0.44m

The effort is =FN=FN

The acceleration due to gravity is g=9.8ms^-2g=9.8ms2

Taking moments about the center of the axle

F*0.44=3g*0.03F0.44=3g0.03

F=(3g*0.03)/0.44=2NF=3g0.030.44=2N

The force is F=2NF=2N

The distance is d=2piR=(0.88pi)md=2πR=(0.88π)m

The work is W=Fxxd=2*0.88pi=5.54JW=F×d=20.88π=5.54J