How do I calculate the centripetal force?

Question

In this experiment, a brown rubber weighs 42.2 grams and was spun at a velocity of 4.66m/s with a radius of 40cm and masses of 200g...the answer should be about 1.96N and I got 2.3.

Can someone confirm or deny this?

Answer 1

I got the same answer as you, $$ F={mv^2\over r}=(42.2/1000)\times(4.66)^2/(40/100)=2.29{\rm Nm} $$