Question

Which among the following statements is true about Huygen's principle
1. Each point on a wavefront is a source of secondary waves
2. Each point on a wavefront is a sink of secondary waves
3. No point on a wavefront is a source of secondary waves
4. None of the above

Answer 1

Correct Answer - Option 1 : Each point on a wavefront is a source of secondary waves

The correct answer is option 1) i.e. Each point in a wavefront is a source of secondary waves.

CONCEPT:

Huygens' concepts of secondary wavelets:

• Huygen’s principle states that every point on the wavefront may be considered as a source of secondary spherical wavelets that spread out in the forward direction at the speed of light.
  • The new wavefront is the tangential surface of all these secondary wavelets.
  • Secondary sources start making their own wavelets, these waves are similar to that of the primary source
  • It states that each point on a wavefront is a source of wavelets, which spread forward with the same speed.

• Wavefront: A wavefront is a surface or a line on which the disturbance at every point has the same phase.
• Wavelets: It is a wave-like oscillation with an amplitude that starts at zero, increases, and then decreases back to zero.

EXPLANATION:

• Huygens's principle states that each point on a wavefront is a source of wavelets, which spread forward with the same speed.