Waves Basics
Physics · तरंगों की मूल बातें
📋Quick Overview
A wave is a disturbance that transfers energy from one point to another WITHOUT transferring matter. When you throw a stone in water, ripples (waves) move outward but water itself doesn't travel — it just moves up and down. There are two main types: Transverse and Longitudinal waves. The wave equation v = f × λ connects speed, frequency and wavelength.
📖Transverse vs Longitudinal Waves
📖Wave Properties
| Property | Symbol | Definition | SI Unit |
|---|---|---|---|
| Amplitude | A | Maximum displacement from rest position | Meter (m) |
| Wavelength | λ (lambda) | Distance between two consecutive crests or troughs | Meter (m) |
| Frequency | f | Number of waves per second | Hertz (Hz) |
| Time Period | T | Time for one complete wave (T = 1/f) | Second (s) |
| Velocity | v | Speed of wave (v = f × λ) | m/s |
📖Electromagnetic Spectrum
Electromagnetic (EM) waves do NOT need a medium — they travel through vacuum. All EM waves travel at the speed of light (3 × 10⁸ m/s). They differ in frequency and wavelength. The EM spectrum from LONGEST wavelength to SHORTEST: Radio → Microwave → Infrared → Visible → Ultraviolet → X-ray → Gamma ray.
Visible light (VIBGYOR) is just a tiny part of the EM spectrum. Red has longest wavelength; Violet has shortest wavelength (but highest frequency) among visible colors.