# A model train with a mass of 3 kg is moving along a track at 16 (cm)/s. If the curvature of the track changes from a radius of 15 cm to 18 cm, by how much must the centripetal force applied by the tracks change?

##### 1 Answer
Feb 11, 2017

The answer is $= 2.56 N$

#### Explanation:

The centripetal force is

$F = \frac{m {v}^{2}}{r}$

The variation in centripetal force is

$\Delta F = \frac{m {v}^{2}}{\Delta r}$

$= \frac{3 \cdot {\left(0.16\right)}^{2}}{0.18 - 0.15}$

$= \frac{3 \cdot 0.16 \cdot 0.16}{0.03}$

$= 2.56 N$