A model train, with a mass of #3 kg#, is moving on a circular track with a radius of #2 m#. If the train's rate of revolution changes from #5/3 Hz# to #1/8 Hz#, by how much will the centripetal force applied by the tracks change by?

1 Answer
Jan 23, 2018

The change in centripetal force is #=654.3N#

Explanation:

The centripetal force is

#F=(mv^2)/r=mromega^2N#

The mass of the train, #m=(3)kg#

The radius of the track, #r=(2)m#

The frequencies are

#f_1=(5/3)Hz#

#f_2=(1/8)Hz#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mromega_1^2=mr*(2pif_1)^2=3*2*(2pi*5/3)^2=658.0N#

#F_2=mromega_2^2=mr*(2pif_2)^2=3*2*(2pi*1/8)^2=3.7N#

#DeltaF=F_1-F_2=658-3.7=654.3N#