<span>The medium in which it travels through</span>
LAPA HDIDOSHSUWJWVWIHDHDOSSHSVWIME
Explanation:
It is given that,
Frequency of the laser light, 
Time, 
(a) Let 
is the wavelength of this light. It can be calculated as :
or
(b) Let n is the number of the wavelengths in one pulse. It can be calculated as :
n = 13440
Hence, this is the required solution.
<h2>Answer: True
</h2>
The <u>Doppler effect</u> refers to the change in a wave perceived frequency when the emitter of the waves, and the receiver (or observer in the case of light) move relative to each other.
In other words, it is the variation of the frequency of a wave due to the relative movement of the source of the wave with respect to its receiver.
It should be noted that this effect bears its name in honor of the Austrian physicist <u>Christian Andreas Doppler</u>, who in 1842 proposed the existence of this effect for the case of light in the stars. Another important aspect is that the effect occurs in all waves (including light and sound). However, it is more noticeable to humans with sound waves.
