An object with a mass of #7 kg# is revolving around a point at a distance of #7 m#. If the object is making revolutions at a frequency of #9 Hz#, what is the centripetal force acting on the object?

1 Answer
Jan 9, 2018

Answer:

OK, there are two equations for centripetal force, both useful, we need the one that has #omega# in it as we are given a frequency, not a linear velocity.

Explanation:

The equations are:

#F = (mv^2)/r# and #F = momega^2r# where #omega = 2pif# and is called the angular velocity (but confusingly, also the angular frequency.)

First, we find #omega = 2pif = 2xx3.14xx9 = 56.52# rad/s

Next the force, #F = momega^2r = 7xx(56.52^2) xx 7 = 156 531#N

I’d quote this as #F = 160,000#N given the data you have.