A Circular Motion Question?

Question

I ball of mass 0.1 grams is tied to a 30cm long string.

It rotates in a horizontal circular orbit of radius 15cm. Calculate the Angular Velocity of the ball.

(I think the mass of the ball isn't required in solving this

PS: I got the answer of 5.77 rads/sec.)

Thanks in advance

Answer 1

The string makes an angle of Θ = 30° with the vertical. (Θ = arcsin(15/30))

r*w²/g = tan30° → w² = tan30°*g/r = tan30°*9.8/.15

w = 6.14 rad/sec

Right; mass doesn't enter into this problem.