Answered

The speed, wavelength, and frequency of a wave are related by what equation?

A. Frequency [tex]$=$[/tex] speed + wavelength
B. Speed [tex]$=$[/tex] wavelength [tex]$ \times $[/tex] frequency
C. Speed [tex]$=$[/tex] wavelength - frequency
D. Wavelength [tex]$=$[/tex] speed [tex]$ \times $[/tex] frequency



Answer :

Sure, let's explore the relationships between the speed, wavelength, and frequency of a wave.

The speed [tex]\( v \)[/tex] of a wave is related to its wavelength [tex]\( \lambda \)[/tex] (the distance between successive crests or troughs) and its frequency [tex]\( f \)[/tex] (the number of oscillations per unit time).

The fundamental relationship between these quantities is:
[tex]\[ \text{Speed} = \text{Wavelength} \times \text{Frequency} \][/tex]

Given this understanding, let's review the options provided:

1. Frequency = speed + wavelength

This option suggests that frequency is the sum of speed and wavelength, which doesn't make sense dimensionally. Frequency (measured in Hz or [tex]\( \text{s}^{-1} \)[/tex]) cannot simply be added to a speed (measured in meters/second) and a wavelength (measured in meters).

2. Speed = wavelength × frequency

This option correctly matches the fundamental relationship. The speed of a wave is the product of its wavelength and its frequency. Dimensionally, this makes sense as well:

[tex]\[ \text{Speed (meters/second)} = \text{Wavelength (meters)} \times \text{Frequency (1/second)} \][/tex]

Thus, this relationship is accurate.

3. Speed = wavelength - frequency

This option is incorrect because speed is not the difference between wavelength and frequency. Similar to option 1, subtracting a frequency (1/second) and wavelength (meters) does not create a meaningful or dimensionally consistent result for speed.

4. Wavelength = speed × frequency

This option is incorrect as well according to our wave relationship. The correct relationship is speed = wavelength × frequency, not wavelength = speed × frequency. The units also don't match properly using this formula.

Given our analysis, the correct relationship is:
[tex]\[ \text{Speed} = \text{Wavelength} \times \text{Frequency} \][/tex]

Thus, the correct option is:
[tex]\[ \boxed{2} \][/tex]