Question

For a wave, which of the following products is equal to unity?

• A. Frequency $\times$ Amplitude
• B. Frequency $\times$ Time period
• C. Amplitude $\times$ Time period
• D. Frequency $\times$ Wavelength

Answer 1

The correct option is B Frequency $\times$ Time period

Frequency (f) is the number of waves that pass through a point per second, or the number of oscillations a particle makes in one second.
Time period (T) is the time taken for one wave to pass through a point.
Hence, $f=\frac{1}{T}$
$⟹f\times T=1$