Free mock exam
Fibre Optics Mock Exam
Free fibre optics mock exam. 25 questions from a 250-question bank covering how light travels through optical fibre, singlemode and multimode fibre types including OM4, cable construction, connectors and splicing, installation practice for inside and outside plant, standards and design, attenuation and dispersion, and fault finding.
- Questions
- 30
- Time limit
- 35 min
- Pass mark
- 70% · 21/30
- Question bank
- 250
Free, no sign-up. Retake as many times as you like — different questions each time.
Sample questions
01What is the phenomenon that allows light to travel through an optical fibre?
- ARayleigh scattering within the core
- BTotal internal reflection
- CDiffraction around the cladding boundary
- DRefraction into the cladding layer
Why: Total internal reflection occurs when light hits the core/cladding boundary at an angle greater than the critical angle, causing it to reflect back into the core rather than escaping.
02What is the typical core diameter of singlemode fibre?
- A62.5 micrometres
- B125 micrometres
- C50 micrometres
- D8-9 micrometres
Why: Singlemode fibre has a small core diameter of 8-9 micrometres (typically 9µm for OS2), which allows only one mode of light to propagate. The 125µm dimension refers to the cladding diameter.
03Which fibre type is best suited for long-distance telecommunications applications?
- AOM4 multimode
- BOS2 singlemode
- COM1 multimode
- DOM3 multimode
Why: OS2 singlemode fibre has the lowest attenuation (0.35 dB/km at 1310nm, 0.22 dB/km at 1550nm) and no modal dispersion, making it ideal for long-distance transmission.
Common questions
Is the Fibre Optics mock exam free?
Yes — 100% free, no sign-up needed. Questions are pulled at random from a substantial bank, with a worked explanation on every question after you submit.
Can I retake the mock exam?
Yes. Every attempt picks a different random selection and reshuffles the options, so each retake gives you genuinely new questions. No limit on retakes.
Does this count towards the real qualification?
No — this is independent practice material. To gain the actual qualification you need to sit the official assessment through an approved provider.
