The graph above depicts a wave’s amplitude as a function of distance. If the wave has a speed of $600\ \mathrm{\displaystyle \frac{m}{s}}$, which off the following is the best approximation of the wave’s frequency?
A) $50\ \mathrm{Hz}$
B) $100\ \mathrm{Hz}$
C) $200\ \mathrm{Hz}$
D) Cannot be determined without additional information.
A) $50\ \mathrm{Hz}$
B) $100\ \mathrm{Hz}$
C) $200\ \mathrm{Hz}$
D) Cannot be determined without additional information.
The distance from one crest to another is the wavelength. In this case, that distance is 6 m. Furthermore, you know that
$$v=f\lambda $$
for any wave. Solving for f gives
$$f=\frac{v}{\lambda }$$
Plugging in the known values gives
$$f=\frac{(600)}{(6)}=100\ \mathrm{Hz}$$