Telecommunications quiz

More questions about Telecommunications

These visible examples show the question style. LearnClash turns the full topic into ranked duels and spaced repetition.

1. 1 Easy

   Which word stands for X in the NATO alphabet?

   Answer: X-ray

   Why: The code words were picked after hundreds of thousands of comprehension tests with speakers of 31 nationalities.

2. 2 Medium

   Where does a corded landline get its power?

   Answer: Phone line

   Why: On classic copper lines the exchange sends about 48 volts from battery-backed supplies, so corded phones work through a home power cut.

3. 3 Hard

   What element amplifies light in undersea fiber cables?

   Answer: Erbium

   Why: Erbium-doped fiber boosts the light itself, with no need to turn the signal back into electricity at each repeater.

4. 4 Easy

   How do radio broadcasts travel?

   Answer: As electromagnetic waves

   Why: Radio waves cross empty space, where sound cannot travel, which is why spacecraft talk to Earth by radio.

5. 5 Medium

   Who was the film star behind frequency hopping?

   Answer: Hedy Lamarr

   Why: Her 1942 patent with composer George Antheil hopped among 88 frequencies, one for each key on a piano, to beat jamming.

6. 6 Hard

   How many times a second is standard digital phone audio sampled?

   Answer: 8,000

   Why: Sampling needs more than twice the highest pitch kept, and phone audio stops near 3,400 Hz, so 8,000 a second is plenty.