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 #5/4 Hz# to #3/8 Hz#, by how much will the centripetal force applied by the tracks change by?

1 Answer
Jan 15, 2018

Answer:

The change in centrpetal force #=336.8N#

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=(5/4)Hz#

#f_2=(3/8)Hz#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mromega_1^2=mr*(2pif_1)^2=3*2*(2pi*5/4)^2=370.1N#

#F_2=mromega_2^2=mr*(2pif_2)^2=3*2*(2pi*3/8)^2=33.3N#

#DeltaF=F_1-F_2=370.1-33.3=336.8N#