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

1 Answer
Mar 6, 2016

Answer:

#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 #666666#s