Question

A model train, with a mass of `16 kg`, is moving on a circular track with a radius of `9 m`. If the train's kinetic energy changes from `40 j` to `9 j`, by how much will the centripetal force applied by the tracks change by?

Answer 1

6.88 N.

Explanation:

Here,
In 1st case,

`KE =1/2 mv^2`
`40*2 = mv^2`
`mv^2/r = 80/9`
`Fc = 80/9 N`

In 2nd case,

`m v^2/r = 2 * 9/9 = 2`
`Fc = 2 N`

`triangle Fc = 80/9- 2 = 62/9 = 6.88 N`

Thank you!!!