Question

A model train, with a mass of `2 kg`, is moving on a circular track with a radius of `2/3 m`. If the train's rate of revolution changes from `1/2 Hz` to `6/5 Hz`, by how much will the centripetal force applied by the tracks change by?

Answer 1

The change in centripetal force is `=62.6N`

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=(2/3)m`

The frequencies are

`f_1=(1/2)Hz`

`f_2=(6/5)Hz`

The variation in centripetal force is

`DeltaF=F_2-F_1`

`F_1=mromega_1^2=mr*(2pif_1)^2=2*2/3*(2pi*1/2)^2=13.2N`

`F_2=mromega_2^2=mr*(2pif_2)^2=2*2/3*(2pi*6/5)^2=75.8N`

`DeltaF=F_1-F_2=75.8-13.2=62.6N`