Question

the depth of the pit in a compact disc is ---------
option
1. 180 degree in phase
2. 1/4 of the wavelength
3. 360 degree out of phase
4. 1/2 of the wavelength​

Answer 1

Answer:

1/2 of the wavelength is the depth of pitbin compact disc

Answer 2

COMPACT DISC

The depth of the pit in a compact disc is 1/2 OF THE WAVELENGTH

EXPLANATION :

* A semi-conductor laser with a wavelength of 700 nm travels through a plastic substrate with a refractive index of 1.8 to read a CD (compact disc) from the bottom.

* When the beam hits a 0 pit, some of the beam is reflected from the pit, while the rest is reflected from the flat zone.

*The two beams collide with one another. Pits generate bumps when read because they are recessed into the top layer of the disc and read through the translucent polycarbonate base.