Lecture 13: Properties of Waves

These flashcards cover key vocabulary and concepts related to the properties of waves as discussed in Lecture 13.

What is a wave?

A disturbance that transfers energy from one point to another without transferring matter.

Crest

The highest point of a transverse wave.

Trough

The lowest point of a transverse wave.

Amplitude

The maximum displacement of a particle from the rest position.

Wavelength (λ)

The distance between two successive, identical points on a wave.

Frequency (f)

The number of complete waves (cycles) that pass a point per second.

Period (T)

The time it takes for one complete wave cycle to pass a point.

Rest Position

The equilibrium position of the medium when no wave is present.

Transverse Wave

A wave where the disturbance is perpendicular to the direction the wave travels.

Longitudinal Wave

A wave where the disturbance is parallel to the direction the wave travels.

Velocity (v)

The speed of a wave, calculated using the formula v = f × λ.

Reflection

When a wave bounces off a barrier.

Refraction

The bending of a wave as it passes from one medium into another, caused by a change in its speed.

Diffraction

The bending of waves around obstacles or the spreading out of waves through an opening.

Interference

When two or more waves combine.

Constructive Interference

Waves add together to create a larger amplitude (crests meet crests).

Destructive Interference

Waves subtract from each other to create a smaller amplitude (a crest meets a trough).

Compression

Where particles in a longitudinal wave are close together.

Rarefaction

Where particles in a longitudinal wave are spread out.

Unit of Frequency

Hertz (Hz), equivalent to 1 wave/second.

Key relationship between Frequency (f) and Period (T)

They are inverses; f = 1/T and T = 1/f.

Example of Reflection

An echo is the reflection of a sound wave.

Example of Refraction

A straw looks bent in a glass of water.

Example of Diffraction

Hearing music from another room even when the door is slightly open.

Energy of the wave

Related to amplitude; higher amplitude means more energy.

Medium

Substance through which a wave travels (e.g., water, air, string).

Wave behavior

How waves interact with boundaries and other waves.