# A model train, with a mass of #4# #kg#, is moving on a circular track with a radius of #3# #m#. If the train's kinetic energy changes from #12# #J# to #48# #J#, by how much will the centripetal force applied by the tracks change by?

##### 1 Answer

Centripetal force changes from

#### Explanation:

Kinetic energy

The initial velocity will be given by

When an object moves in a circular path at a constant speed, it experiences a centripetal force is given by

Centripetal force at the beginning will be

Hence centripetal force changes from