An object with a mass of #2 kg# is hanging from an axle with a radius of #2 cm#. If the wheel attached to the axle has a radius of #8 cm#, how much work would it take to turn the wheel a length equal to the circumference of the axle?

1 Answer
Mar 23, 2018

The work #=2.46J#

Explanation:

www.odicis.org

The load is #L=2gN#

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

The radius of the wheel is #R=0.08m#

The effort is #=FN#

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

Taking moments about the center of the axle

#F*0.08=2g*0.02#

#F=(2g*0.02)/0.08=4.9N#

The force is #F=4.9N#

The distance is #d=2piR=2pi*0.08=0.16pim#

The work done is

#W=F*d=4.9*0.16pi=2.46J#