A laser is worked by electromagnetic radiation. The term "laser" originated as an acronym for "light amplification by stimulated emission of radiation".








<h3>☯ <u>By using formula of Lens</u> </h3>











<h3>☯ <u>Now, Finding the magnification </u></h3>





<h3>☯ <u>Hence</u>,

</h3>


Answer: The sound will change due to changes in frequency and the wavelength of the airplane.
Explanation: Let assume that the observer is at a stationary position. The wavelength of the sound from the airplane reduces and the frequency increases as the plane is moving toward the observer. As the airplane passes by, that is, moving away from the observer, the frequency starts to reduce while the wavelength of the sound starts to increase.
The sound that the observer hears will change base on the illustration above.
Answer:
-75 cm
Explanation:
At l ; F = 350 Hz
At l + 15 cm ; F = 280 Hz
I = 350
I + 15 = 280
280I = 350(I + 15)
280I = 350I + 5250
280I - 350I = 5250
-70I = 5250
I = - 75cm
The length is - 75 cm