Physics
posted by Ted .
A stopper tied to the end of a string is swung in a horizontal circle. If a mass of the stopper is 13.0 g, and the string is 93.0 cm, and the stopper revolves at a constant speed 10 times in 11.8 secs, what is the tension on the string?
I tried solving this question using the formula T=mv^2/r. To use this i have to find the v. To find the v, i want to use v=2pi R/t. t in this formula is period. I'm confused on how to find t. Pls help

T=t/N=11.8/10=1.18 s
ω=2π/T=2π/1.18=5.32 rad/s
T=mv²/R=mω²R=0.013•5.32 ²•0.93=0.34 N