Calculate the speed (in m/sec) of a wave with a wavelength of 2.1 meters and a period of 9.4 second.

Wave speed = (wavelength) x (frequency)

We know the wavelength, but we don't know the frequency. How can we find the frequency ?  "Here frequency frequency."

We know the period, and frequency is just (1 / period).  So . . .

Wave speed = (wavelength) / (period)

Wave speed = (2.1 meters) / (9.4 seconds)

Wave speed = (2.1 / 9.4) m/s

Wave speed = 0.223 m/s

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