Question

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?

Answer 1

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`