Multiple choice

In which of the following electronic devices is the phenomenon of thermionic emission used?

(1) Diode valve (2) Radio (3) Stopwatch

  1. Only (3)

  2. Both (2) and (3)

  3. Only (1)

  4. Both (1) and (2)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In diode valve and radio, the phenomenon of thermionic emission is used.