ETA Fiber Optics Certification Questions
with Correct Answers 2026-2027
Light is electromagnetic energy with a frequency and a wavelength compa
red to radio waves. - CORRECT ANSWER -Higher, Shorter
What type of light is used in Fiber Optic Transmissions - CORRECT ANSWER -Infrared or IR
What are the four items needed for a Fiber Optic System to work? - CORRECT ANSWER -
Transmitter, Fiber Cable, Receiver, Connectors
1mW is the same as what in dBM? - CORRECT ANSWER -0 or absolute power
How is power measured in fiber? - CORRECT ANSWER -mW or dBM
Propagation - CORRECT ANSWER -
light is reflected off a body and is return to its original emission point, the law of propagation for
the return trip is the original trip.
wavelength - CORRECT ANSWER -
Horizontal distance between the crests or between the troughs of two adjacent waves
Frequency - CORRECT ANSWER -
the number of complete wavelengths that pass a point in a given time
What fiber optic wavelength has the lowest loss? - CORRECT ANSWER -1550 um
What wavelength windows are used for most communications? - CORRECT ANSWER -
850, 1330, 1550
, What year was the first fiber optic cable used in the communication telephone system? -
CORRECT ANSWER -1977
What light source is used for single mode? - CORRECT ANSWER -Laser Diode LD
What two light sources are used with multimode? - CORRECT ANSWER -
Light Emitting Diode (LED)
Vertical Cavity Surface Emitting Laser (VCSEL)
All wavelengths of light travel at the same speed. True or False - CORRECT ANSWER -False
Which type of fiber has the largest core size? - CORRECT ANSWER -Multi-mode
What is OSHA responsible for? - CORRECT ANSWER -
the identification of various hazards present in the workplace and for the creation of rules and r
egulations to minimize exposure to such hazards
What are two ways to reduce modal dispersion? - CORRECT ANSWER -
Smaller Core and use graded index fiber
What happens to the wavelength in optical fiber when the number of modes increases? -
CORRECT ANSWER -Gets shorter
decreases
When does Fresnel reflection occur - CORRECT ANSWER -
A small portion of the incident light is reflected back into the source fiber at the fiber interface.
with Correct Answers 2026-2027
Light is electromagnetic energy with a frequency and a wavelength compa
red to radio waves. - CORRECT ANSWER -Higher, Shorter
What type of light is used in Fiber Optic Transmissions - CORRECT ANSWER -Infrared or IR
What are the four items needed for a Fiber Optic System to work? - CORRECT ANSWER -
Transmitter, Fiber Cable, Receiver, Connectors
1mW is the same as what in dBM? - CORRECT ANSWER -0 or absolute power
How is power measured in fiber? - CORRECT ANSWER -mW or dBM
Propagation - CORRECT ANSWER -
light is reflected off a body and is return to its original emission point, the law of propagation for
the return trip is the original trip.
wavelength - CORRECT ANSWER -
Horizontal distance between the crests or between the troughs of two adjacent waves
Frequency - CORRECT ANSWER -
the number of complete wavelengths that pass a point in a given time
What fiber optic wavelength has the lowest loss? - CORRECT ANSWER -1550 um
What wavelength windows are used for most communications? - CORRECT ANSWER -
850, 1330, 1550
, What year was the first fiber optic cable used in the communication telephone system? -
CORRECT ANSWER -1977
What light source is used for single mode? - CORRECT ANSWER -Laser Diode LD
What two light sources are used with multimode? - CORRECT ANSWER -
Light Emitting Diode (LED)
Vertical Cavity Surface Emitting Laser (VCSEL)
All wavelengths of light travel at the same speed. True or False - CORRECT ANSWER -False
Which type of fiber has the largest core size? - CORRECT ANSWER -Multi-mode
What is OSHA responsible for? - CORRECT ANSWER -
the identification of various hazards present in the workplace and for the creation of rules and r
egulations to minimize exposure to such hazards
What are two ways to reduce modal dispersion? - CORRECT ANSWER -
Smaller Core and use graded index fiber
What happens to the wavelength in optical fiber when the number of modes increases? -
CORRECT ANSWER -Gets shorter
decreases
When does Fresnel reflection occur - CORRECT ANSWER -
A small portion of the incident light is reflected back into the source fiber at the fiber interface.
