Question

A model train with a mass of `3 kg` is moving along a track at `12 (cm)/s`. If the curvature of the track changes from a radius of `4 cm` to `8 cm`, by how much must the centripetal force applied by the tracks change?

Answer 1

The change in centripetal force is `=0.54N`

Explanation:

The centripetal force is

`vecF_C=(mv^2)/r*vecr`

The mass is of the train `m=3kg`

The velocity of the train is `v=0.12ms^-1`

The radii of the tracks are

`r_1=0.04m`

and

`r_2=0.08m`

The variation in the centripetal force is

`DeltaF=F_2-F_1`

The centripetal forces are

`||F_1||=3*0.12^2/0.04=1.08N`

`||F_2||=3*0.12^2/0.08=0.54N`

`DeltaF=F_1-F_2=1.08-0.54=0.54N`