OCN-Q11

1. What defines a single-mode fiber?

• A) It supports multiple light modes.

• B) It supports only one light mode.

• C) It has a large core diameter.

• D) It has a high numerical aperture.

2. Which of the following is a typical core diameter for single-mode fibers?

• A) 50 µm

• B) 62.5 µm

• C) 8-10 µm

• D) 100 µm

3. The cutoff wavelength of a single-mode fiber is the wavelength:

• A) Below which the fiber supports multiple modes

• B) Above which the fiber supports multiple modes

• C) Below which the fiber supports a single mode

• D) Above which the fiber supports a single mode

4. Which of the following is true about the cutoff wavelength in single-mode fibers?

• A) It is always in the visible light spectrum

• B) It determines the maximum wavelength for single-mode operation

• C) It determines the minimum wavelength for single-mode operation

• D) It is not relevant to single-mode fibers

5. What happens if the operating wavelength is shorter than the cutoff wavelength in a single-mode fiber?

• A) The fiber supports only one mode

• B) The fiber becomes multimode

• C) The fiber ceases to function

• D) The fiber supports no modes

6.Which parameter is most critical in determining the cutoff wavelength of a fiber?

• A) Core diameter

• B) Numerical aperture

• C) Cladding refractive index

• D) Length of the fiber

7.What is the consequence of operating a fiber below its cutoff wavelength?

• A) The fiber supports only the fundamental mode

• B) The fiber exhibits chromatic dispersion

• C) The fiber supports higher-order modes

• D) The fiber's attenuation increases drastically