Question

With which of the following is the tape of the tape recorder coated?

  1. Copper sulphate
  2. Ferromagnetic powder
  3. Zinc oxide
  4. Mercury

Answer:

Option B: Ferromagnetic powder

Detailed Solution:

The correct answer is “Ferromagnetic powder”.

This ferromagnetic powder, typically iron oxide, is essential for recording audio. When the tape passes over the recording head, the magnetic field aligns the particles on the tape, creating a magnetic pattern that represents the sound.