Beats are:

  1. regular rises and falls in loudness when two waves of slightly different frequency interfere
  2. the sound of a drum only
  3. echoes of a sound
  4. a change in pitch due to motion
Answer

A) regular rises and falls in loudness when two waves of slightly different frequency interfere

Pulsation due to interference. SLO P-11-D-15 · Understanding

Physics MCQ · More Superposition, Stationary Waves and Beats MCQs · Practise