posted by Matt .
A 0.40-kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 1.3 m on a frictionless surface. If the cord will break when the tension in it exceeds 60 N, what is the maximum speed the ball can have? How would your answer be affected if there were friction?
I already found the maximum speed to be about 14 m/s. I'm stuck on the second part of the question which asks how this answer would be affected if there were friction? And please don't just tell me how it would change, tell me why it would change.
friction would assist tension, as it resists motion along the chord
60N<mv^2/r - friction