A 200g block on a 50cm long string swings in a circle, it's frictionless and 75rpm. What is its speed and tension on string

Angular velocity = (75x2pie) / 60

=2.5pie ras^-1

linear velocity (or speed) at end of string, v = radius x angular velocity

v = 0.5 x 2.5pie

v=3.93 ms^-1

tension of string (I beleve is centeral force aplied by string), F = (mv^2) / r

F = (0.2 x 3.93^2) / 0.5

F=6.18 N

(sorry if wrong)