Physics
posted by Mike .
A 0.40kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 2.0m on a frictionless horizontal surface.
If the cord will break when the tension in it exceeds 75N, what is the maximum speed the ball can have?

T(max) = mv²/R.
v=sqrt(R•T(max)/m) =
=sqrt(2•75/0.4)=19.4 m/s