# An object with a mass of 15 kg is revolving around a point at a distance of 16 m. If the object is making revolutions at a frequency of 15 Hz, what is the centripetal force acting on the object?

Jan 29, 2017

I got:
${F}_{c} = 1 , 932 , 407 N$

#### Explanation:

We start remembering that centripetal force is:

${F}_{c} = m {v}^{2} / r$

To evaluate the velocity we use frequency and we consider that our object is making 15 revolutions in 1 second so we get that it takes:
$\frac{1}{15} = 0.07 s$ to complete one revolution that represents a distance along a circle of $2 \pi r = 2 \cdot 3.14 \cdot 16 = 100.53 \approx 100.5 m$.
Velocity will then be: $v = \frac{100.5}{0.07} = 1435.7 \frac{m}{s}$

So we get:
${F}_{c} = 15 \cdot {\left(1435.7\right)}^{2} / 16 = 1 , 932 , 407 N$