A model train, with a mass of #4 kg#, is moving on a circular track with a radius of #7 m#. If the train's rate of revolution changes from #1/6 Hz# to #1/3 Hz#, by how much will the centripetal force applied by the tracks change by?

1 Answer
Jan 7, 2018

Answer:

The change in centripetal force is #=92.11N#

Explanation:

The centripetal force is

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

The mass of the train, #m=(4)kg#

The radius of the track, #r=(7)m#

The frequencies are

#f_1=(1/6)Hz#

#f_2=(1/3)Hz#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mromega_1^2=mr*(2pif_1)^2=4*7*(2pi*1/6)^2=30.71N#

#F_2=mromega_2^2=mr*(2pif_2)^2=4*7*(2pi*1/3)^2=122.82N#

#DeltaF=F_1-F_2=122.82-30.71=92.11N#