Question

For the simple harmonic motion equation d=9cos (pi/2)t), what is the frequency?

Please explain. Thank you!

Answer 1

Here's an example:
For cos(t), t going from 0 to 2pi is one period. If I change the function to cos(2t), then t going from 0 to pi makes (2t) go from 0 to 2pi. So now the period is just pi.

\(\omega t=(2\pi f)t=(\pi /2)t\)
Can you work it out from there?

Answer 2

@YanaSidlinskiy would the answer be 1/4