An object with a mass of 8 kg8kg is hanging from an axle with a radius of 5 cm5cm. If the wheel attached to the axle has a radius of 65 cm65cm, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Jul 1, 2017

The work is =1.89J=1.89J

Explanation:

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The load L=(8g)NL=(8g)N

Radius of axle r=0.05mr=0.05m

Radius of wheel R=0.65mR=0.65m

Taking moments about the center of the axle

F*R=L*rFR=Lr

F*0.65=8*g*0.05F0.65=8g0.05

F=(8*g*0.05)/0.65=6.03NF=8g0.050.65=6.03N

The force is F=6.03NF=6.03N

The distance is d=2pir=0.1pi=0.31md=2πr=0.1π=0.31m

The work is

W=F*d=6.03*0.31=1.89JW=Fd=6.030.31=1.89J