Question

A dog sits 1.5 m from the center of a merry go round with a tangential speed of 2.5 m/s, what is the magnitude of the force that maintains the dog’s circular motion if the dog’s mass is 10kg?

Answer 1

We can find the magnitude of the force that maintains the dog’s circular motion from the definition of the centripetal force:
F_c=ma_c=m v^2/r,
here, F_c is the centripetal force that maintains the dog’s circular motion, m is the mass of the dog, a_c is the centripetal acceleration, v is the tangential speed of the dog and r is the distance of the dog from the center of the merry-go-round.
Then, from this formula we can find the centripetal force:
F_c=m v^2/r=10 kg∙(2.5 m/s)^2/(1.5 m)=41.6 N.