A model train, with a mass of 2 kg, is moving on a circular track with a radius of 3 m. If the train's kinetic energy changes from 16 j to 0 j, by how much will the centripetal force applied by the tracks change by?

1 Answer
Sep 1, 2017

The centripetal force is =10.67N

Explanation:

The centripetal force is

F=(mv^2)/r

The kinetic energy is

KE=1/2mv^2

The variation of kinetic energy is

Delta KE=1/2mv^2-1/2m u^2

=1/2m(v^2-u^2)

The mass is m=2kg

The radius is r=3m

The variation of centripetal force is

DeltaF=m/r(v^2-u^2)

DeltaF=2m/r1/2(v^2-u^2)

=(2)/r*1/2m(v^2-u^2)

=(2)/r*Delta KE

=2/3*(16-0)N

=10.67N