A model train with a mass of #5 kg# is moving along a track at #4 (cm)/s#. If the curvature of the track changes from a radius of #16 cm# to #2 cm#, by how much must the centripetal force applied by the tracks change?

1 Answer
Apr 2, 2016

0.35N

Explanation:

We have that:

  • #m=5kg#
  • #v=4 cm s^-1=0.04ms^-1#
  • #r_1 =16cm = 0.16m #
  • #r_2 = 2cm = 0.02m#

The centripetal force is given by:

#F = (mv^2)/r#

Thus we can work out the change in centripetal force:

#DeltaF = F_2-F_1=(mv^2)/r_2 -( mv^2)/r_1#

#=((5)(0.04)^2)/0.02-((5)(0.04)^2)/0.16=0.35N#