Class 11 Physics Chapter 14 Waves – Revision Notes

Waves in this chapter are split into transverse and longitudinal types, described by the equation y=A sin(kx−ωt) and the relation v=fλ. Superposition then produces standing waves, with their characteristic nodes and antinodes, and beats when two frequencies interfere.

Last Updated: September 23, 2026

Wave Basics

• Transverse vs longitudinal waves.
• y=A sin(kx−ωt); v=fλ=ω/k.

Wave Speed

• On a string: v=√(T/μ).

Superposition

• Standing waves: nodes (zero displacement), antinodes (max displacement); f_n=nv/2L.
• Beats: f_beat=|f1−f2|.

One-Line Summary

Waves transport energy through a medium via oscillating particles, with superposition of waves producing phenomena like standing waves and beats.

Quick visual: a worked diagram from the full Solutions page, for reference.

Frequently Asked Questions

What is the fundamental difference between transverse and longitudinal waves?
In a transverse wave, particles of the medium vibrate perpendicular to the direction of wave propagation, like on a stretched string, while in a longitudinal wave, particles vibrate parallel to the direction of propagation, like sound waves in air.

What is the principle of superposition of waves, and what does it explain?
The principle of superposition states that when two or more waves overlap at a point, the resultant displacement is the sum of the individual displacements, which explains phenomena such as interference and the formation of beats.

Written by Satish

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