A model train, with a mass of 4 kg4kg, is moving on a circular track with a radius of 3 m3m. If the train's kinetic energy changes from 8 j8j to 48 j48j, by how much will the centripetal force applied by the tracks change by?

1 Answer
Mar 6, 2016

deltaF=26.6666666666.......N

Explanation:

Given we have to find the centripetal force on a model train of mass m=4kg which is moving in a circular track of radius r=3m

The centripetal force of a body is F=mv^2/r and the kinetic energy of a body is K=1/2mv^2\implies2k=mv^2
Substituting K in F, we get F=2K/r or deltaF=2/r\deltaK

Here, deltaK=48-8=40J
So, change in centripetal force applied by tracks change by deltaF=2*40/3

Um.....yeah, that's why you end up with 666666s