Question

waves unit test
the formula $v_w = f \cdot \lambda$ describes the relationship between the speed of a wave ($v_w$), and its frequency ($f$) and wavelength ($\lambda$).
for example, if a wave has a frequency of 120 hz and a wavelength of 5m, it would have a speed of 600 m/s.
in one or two sentences, describe what would happen to the frequency of this wave if the wavelength is increased to 10m but the speed stays the same at 600 m/s.
(2 points)

Explanation:

Step1: Rearrange wave speed formula

$f = \frac{v_w}{\lambda}$

Step2: Substitute given values

$f = \frac{600}{10} = 60$ Hz

Step3: Compare new and original frequency

Original $f=120$ Hz, new $f=60$ Hz.

Answer:

When the wavelength is increased to 10 m while the wave speed remains 600 m/s, the frequency of the wave will decrease to 60 Hz, which is half of its original 120 Hz value.