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 #75 cm#, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Aug 9, 2017

Answer:

The work is #=12.93J#

Explanation:

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The load is #L=7gN#

The radius of the axle is #r=0.15m#

The radius of the wheel is #R=0.75m#

The effort is #=FN#

Taking moments about the center of the axle

#F*0.75=7g*0.15#

#F=7g*0.15/0.75=13.72N#

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

The work is

#W=Fd=13.72*0.3pi=12.93J#