A model train with a mass of 4 kg4kg is moving along a track at 21 (cm)/s21cms. If the curvature of the track changes from a radius of 84 cm84cm to 70 cm70cm, by how much must the centripetal force applied by the tracks change?

1 Answer
Aug 30, 2017

The change in centripetal force is =0.042N=0.042N

Explanation:

The centripetal force is

F=(mv^2)/rF=mv2r

The mass, m=(4)kgm=(4)kg

The speed, v=(0.21)ms^-1v=(0.21)ms1

The radius, =(r) m=(r)m

The variation in centripetal force is

DeltaF=F_2-F_1

F_1=mv^2/r_1=4*0.21^2/0.84=0.21N

F_2=mv^2/r_2=4*0.21^2/0.70=0.252N

DeltaF=0.252-0.21=0.042N