A wave on a string?

Question

is described by the wave function

y=(0.1m) sin[(0.5 rad/m)x-(20rad/s)t]

How is the frequency of osciallation of a particular point at x = 2.0 m (in Hz) determined.

Answer 1

The frequency is 20rad/s (the factor multiplying t within the sin or cos function).
If you want that in Hz, which is cycles per second, you should divide by 2pi

20 / 6.28 = 3.18Hz