An object with a mass of #5 kg# is hanging from an axle with a radius of #21 cm#. If the wheel attached to the axle has a radius of #14 cm#, how much work would it take to turn the wheel #25 cm#?

1 Answer
Dec 28, 2017

The work done is #=18.375J#

Explanation:

enter image source here

The load is #L=5gN#

The radius of the axle is #r=0.21m#

The radius of the wheel is #R=0.14m#

The effort is #=FN#

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

Taking moments about the center of the axle

#F*0.14=5g*0.21#

#F=(5g*0.21)/0.14=73.5N#

The force is #F=73.5N#

The distance is #d=0.25m#

The work done is

#W=F*d=73.5*0.25=18.375J#