A model train, with a mass of #6 kg#, is moving on a circular track with a radius of #7 m#. If the train's rate of revolution changes from #4 Hz# to #2 Hz#, by how much will the centripetal force applied by the tracks change by?

1 Answer
Dec 31, 2017

Answer:

The change in centripetal force is #=19897.1N#

Explanation:

The centripetal force is

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

The mass of the train, #m=(6)kg#

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

The frequencies are

#f_1=4Hz#

#f_2=2Hz#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mromega_1^2=mr*(2pif_1)^2=6*7*(2pi*4)^2=26529.5N#

#F_2=mromega_2^2=mr*(2pif_2)^2=6*7*(2pi*2)^2=6632.4N#

#DeltaF=F_1-F_2=26529.5-6632.4=19897.1N#