Understanding Waves: Sound and Light

Introduction to Waves Waves are vibrations that transfer energy from one place to another without the transfer of matter. There are two main types of waves: Tra...

Introduction to Waves

Waves are vibrations that transfer energy from one place to another without the transfer of matter. There are two main types of waves:

Transverse Waves

In transverse waves, the vibrations are perpendicular to the direction of wave travel. Examples include:

Light waves
Waves on a string
Water waves

Longitudinal Waves

In longitudinal waves, the vibrations are parallel to the direction of wave travel. Examples include:

Sound waves
Seismic P-waves

Wave Properties

All waves have the following properties:

Amplitude: Maximum displacement from the resting position
Wavelength: Distance between consecutive wave peaks
Frequency: Number of waves passing a point per second
Period: Time taken for one complete wave cycle
Wave Speed: Speed at which the wave travels through a medium

The Electromagnetic Spectrum

The electromagnetic spectrum is the range of all possible electromagnetic radiation frequencies. It includes:

Radio waves: Used for radio and TV broadcasts
Microwaves: Used for communications and microwave ovens
Infrared radiation: Thermal imaging and night vision
Visible light: Enables sight
Ultraviolet radiation: Present in sunlight, can cause sunburn
X-rays: Used for medical imaging and security screening
Gamma rays: Produced by nuclear reactions, very high energy

Sound Waves

Sound waves are longitudinal waves that travel through a medium such as air, water, or solids. They have practical uses such as:

Ultrasound: Used for medical imaging and industrial applications
Echo sounding: Used to measure water depth and detect objects underwater
Seismic waves: Used to study the Earth's interior and detect earthquakes

Worked Example: Calculating Wave Speed

Problem: A wave has a frequency of 5 Hz and a wavelength of 2 m. Calculate its wave speed.

Solution:

Wave speed = Frequency × Wavelength
Given: Frequency = 5 Hz, Wavelength = 2 m
Wave speed = 5 × 2 = 10 m/s