Question

Find the wavelength of a wave traveling at 3.26 e6 m/s with a period of 0.0125 s.

Answer 1

The frequency of a wave is the reciprocal of its period, so for the wave in this problem, its frequency is
$f= \frac{1}{T}= \frac{1}{0.0125 s} =80 Hz$

The basic relationship between wavelength, frequency and speed of a wave is given by:
$\lambda= \frac{v}{f}$
where
$\lambda$ is the wavelength of the wave
v is its speed
f is its frequency

If we plug the numbers given by the problem into this equation, we can find the wavelength of this wave:
$\lambda= \frac{v}{f}= \frac{3.26 \cdot 10^6 m/s}{80 Hz}=4.08 \cdot 10^4 m=40.8 km$