An object with a mass of #3 kg# is hanging from an axle with a radius of #2 cm#. If the wheel attached to the axle has a radius of #15 cm#, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Oct 30, 2017

Answer:

The work is #=3.69J#

Explanation:

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The load is #L=3gN#

The radius of the axle is #r=0.02m#

The radius of the wheel is #R=0.15m#

The effort is #=FN#

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

Taking moments about the center of the axle

#F*0.15=3g*0.02#

#F=3g*0.02/0.15=3.92N#

The force is #F=3.92N#

The distance is #d=2piR=2pi*0.15=0.3pim#

The work is #W=Fd=3.92*0.3pi=3.69J#