A model train with a mass of 5 kg5kg is moving along a track at 4 (cm)/s4cms. If the curvature of the track changes from a radius of 4 cm4cm to 2 cm2cm, by how much must the centripetal force applied by the tracks change?

1 Answer
Feb 3, 2018

The change in ventripetal force is =0.2N=0.2N

Explanation:

The centripetal force is

vecF_C=(mv^2)/r*vecrFC=mv2rr

The mass is of the train m=5kgm=5kg

The velocity of the train is v=0.04ms^-1v=0.04ms1

The radii are

r_1=0.04mr1=0.04m

and

r_2=0.02mr2=0.02m

The variation in the centripetal force is

DeltaF=F_2-F_1

The centripetal forces are

||F_1||=5*0.04^2/0.04=0.2N

||F_2||=5*0.04^2/0.02=0.4N

DeltaF=F_2-F_1=0.4-0.2=0.2N