An object with a mass of #7 kg# is hanging from an axle with a radius of #15 cm#. If the wheel attached to the axle has a radius of #65 cm#, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Jun 6, 2017

Answer:

The work is #=14.9J#

Explanation:

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The load L=(7g)N#

Radius of axle #r=0.15m#

Radius of wheel #R=0.65m#

Taking moments about the center of the axle

#F*R=L*r#

#F*0.65=7*g*0.15#

#F=(7*g*0.15)/0.65=15.83N#

The force is #=15.83N#

The distance is #=2pir=2*0.15*pi=0.3pi#

The work is

#W=F*d=15.83*0.3pi=14.9J#