When a light wave enters a medium of greater density, which of the characteristics below will decrease in the wave.
a
Speed
b
Amplitude
c
Frequency
d
Height
a) Speed
When a light wave enters a medium of greater density, the speed of the wave decreases. This happens because the particles in the medium are closer together and interact with the wave, causing it to slow down.
To understand why the speed decreases, let's consider the equation that relates the speed of light to its frequency and wavelength:
Speed of light = frequency × wavelength
In a vacuum or air, the speed of light is a constant value, but when light enters a medium like water or glass, it slows down due to interactions with the particles in the medium. However, the frequency of the light wave remains constant, as it is determined by the source that produced the light.
Since the speed of light decreases while the frequency stays constant, we can conclude that the wavelength of the light wave also decreases. This means that as the light wave enters a medium of greater density, its characteristics such as amplitude, height, and frequency remain the same, while the speed and wavelength decrease.