Introduction to Waves

Lesson 1

Lesson 1: Introduction to Waves is an interactive resource to learn the introductory content of waves and their physics. This page covers the basics of the anatomy of waves, their movement, and the relationships between their driving forces.

What are Waves?

Overview

Waves are dynamic patterns that transfer energy.

Waves are a repeating, structured motion that move through space and time. This means that if you observe a wave over time, you’ll see recurring features. They are dynamic because they move and change with time and are not a static structure.

Some waves transfer energy by traveling through matter, causing particles in a medium, such as air, water, or solids, to move back and forth as the wave passes through. While other waves can even transfer energy through empty space.

Waves are a repeating, structured motion that move in space and time. They Transfer energy through space by traveling through matter or moving through empty space.

Light behaves like a wave, and sound is a wave.

Waves are dynamic patterns that transfer energy.

The Anatomy of a Wave

Waves are made of their fundamental properties, which define how they function and interact with the world. The four properties of waves we will look at first are amplitude, frequency, velocity, and wavelength.

Amplitude

Frequency

Velocity

Wavelength

Amplitude


Amplitude is the wave's maximum displacement, the higher the amplitude, the more energy the wave carries. The energy of the wave is proportional to the square of the amplitude. It is measured in various units depending on the type of wave.

In light, amplitude affects intensity or brightness. It is commonly measured in electric field strength (Volts per meter, V/m).

In sound, amplitude corresponds to loudness and is expressed as pressure. It is measured in decibels (dB), which represents perceived loudness on a logarithmic scale.

A

A Closer Look

Amplitude is the wave's maximum displacement.

Frequency is the number of wave cycles that pass a given point in a second.

Velocity is the speed of a wave.

Wavelength is the distance between two consecutive points on a wave.

Wavelength vs Frequency

Wavelength and frequency are inversely proportional, meaning that as one increases, the other decreases. This relationship exists because both wavelength and frequency describe different aspects of the same wave: frequency measures how many wave cycles pass a point each second, while wavelength measures the distance between consecutive wave peaks. Since the speed of the wave remains constant, any change in frequency must be balanced by an opposite change in wavelength.


The Equation v=fλ

The relationship between velocity, frequency, and wavelength is represented by the equation v=fλ. It shows that the speed of a wave is equal to its frequency multiplied by its wavelength. This creates a connection between how fast a wave moves and its shape-related properties. This equation is universal, applying to all types of waves, and illustrates how these properties interact with each other.

Conclusion

Waves are dynamic patterns that transfer energy.

Waves move energy from one place to another, like ripples running on water or sound traveling through air.

Light behaves like a wave, and sound is a wave.

Some waves transport energy by moving through matter, traveling through different mediums such as air, water, or solids. But, other waves can even move through empty space.

Understanding waves is the key to understanding how we perceive the world around us, from the light we see, to the sounds we hear, to the force that holds us to our planet.