You swing a marble with mass m attached to the end of a string in a horizontal circle as shown in the figure below. The angle that the string makes with the vertical is
θ = 37°.
(a) Find the speed of the marble when the string is 26.0 cm long.
Ar = v^2/r
The Attempt at a Solution
I solved for the radius by using trig, but now I don't know what to do. Without mass or revloutions, I don't know how to solve form the speed.