An object with a mass of 5 kg5kg is hanging from an axle with a radius of 21 cm21cm. If the wheel attached to the axle has a radius of 14 cm14cm, how much work would it take to turn the wheel 7 cm7cm?

1 Answer
Jan 19, 2018

The work is =5.145J=5.145J

Explanation:

www.odicis.org

The load is L=5gNL=5gN

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

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

The effort is =FN=FN

The acceleration due to gravity is g=9.8ms^-2g=9.8ms2

Taking moments about the center of the axle

F*0.14=5g*0.21F0.14=5g0.21

F=(5g*0.21)/0.14=73.5NF=5g0.210.14=73.5N

The force is F=73.5NF=73.5N

The distance is d=0.07md=0.07m

The work is W=FxxdW=F×d

W=73.5*0.07=5.145JW=73.50.07=5.145J