Question

You dip your finger into a pan of water twice each second, producing waves with crests that are separated by 0.15 m.
a) determine frequency of these water waves in units of Hz??
b) determine the period of these water waves in units of s. ??
c) determine the speed of these water waves in units of m/s??????

Answer 1

Frequency is 2hz
wavelentth is .15m
speed=freq*wavelength

Answer 2

a) Twice per second is 2 Hz. Literally. "Hz" means "per second".
b) The period (in seconds) is one divided by the frequency (in Hz).
c) Wave speed is wavelength (0.15 m in this case) multipied by the frequency.