A model train, with a mass of #2 kg#, is moving on a circular track with a radius of #9 m#. If the train's rate of revolution changes from #5 Hz# to #2 Hz#, by how much will the centripetal force applied by the tracks change by?

1 Answer
Apr 5, 2018

Answer:

The change in centripetal force is #=14922.9N#

Explanation:

The centripetal force is

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

The mass of the train, #m=(2)kg#

The radius of the track, #r=(9)m#

The frequencies are

#f_1=(5)Hz#

#f_2=(2)Hz#

The angular velocity is #omega=2pif#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mromega_1^2=mr*(2pif_1)^2=2*9*(2pi*5)^2=17765.3N#

#F_2=mromega_2^2=mr*(2pif_2)^2=2*9*(2pi*2)^2=2842.4N#

#DeltaF=F_2-F_1=17765.3-2842.4=14922.9N#