An object with a mass of 7 kg7kg is hanging from an axle with a radius of 15 cm15cm. 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
Jun 6, 2017

The work is =14.9J=14.9J

Explanation:

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The load L=(7g)N#

Radius of axle r=0.15mr=0.15m

Radius of wheel R=0.65mR=0.65m

Taking moments about the center of the axle

F*R=L*rFR=Lr

F*0.65=7*g*0.15F0.65=7g0.15

F=(7*g*0.15)/0.65=15.83NF=7g0.150.65=15.83N

The force is =15.83N=15.83N

The distance is =2pir=2*0.15*pi=0.3pi=2πr=20.15π=0.3π

The work is

W=F*d=15.83*0.3pi=14.9JW=Fd=15.830.3π=14.9J