Electromagnetic Waves

Wave

A disturbance that transfers energy without actually moving the matter itself.

Transverse Wave

A type of fwave where particles move perpendicular to the direction of the wave motion.

Mechanical Wave

A type of wave that needs a medium to travel to, like air or water or a solid. Unable to travel through empty space.

Frequency

How many waves pass by a certain point in one second. It is measured with a unit called Hertz(Hz).

Amplitude

The distance between a particle vibrates above or below the rest position.

Wavelength

The length of one complete wave. An easy way to measure from crest to crest or trough to trough.

Rest Position

The flat, middle line where the particles would be resting if there was no wave passing through it at all.

Crest

The very highest point of a traverse wave.

Trough

The very lowest point of a transverse wave.

Compression

An area of high-density in a longitudinal wave, the area where particles are close together.

Rarefraction

An area of low-density in a longitudinal wave, where they spread out.

Wave Speed

How fast a wave travels in a certain amount of time, usually measured in m/s.

Medium

The actual matter(solid, liquid, gas) that a mechanical wave travels through.

Reflection

When a wave hits something it can’t pass through and bounces back.

Transmission

When wave energy, like light, passes straight through a material.

Absorption

When matter takes in wave’s energy instead of letting it pass through or bounce off.

Refraction

When a wave bends at an angle because it enters a new medium and changes speed.

Energy

What a wave carries from one place to another. Waves with bigger amplitudes and high frequencies carry more energy.

Incident Wave

The wave that is approaching a boundary.

Reflected Wave

The wave that bounces off the boundary and remains in the original medium.

Transmitted Wave

The wave that passes into the obstacle or the new medium on the opposite side of the boundary.

Refraction

The changing of direction as a wave passes one medium to another at an angle, the wave changes speed.

Free-End Reflection

The wave energy reaches the end of the medium and a portion is reflected back into the medium. The pulse is not inverted.

Fixed-End Reflection

The wave energy reaches the end of the medium and a portion is reflected back into the medium. The reflected pulse is inverted.

Node

The point on a standing wave that appears stationary.

Antinode

The point on a standing wave where the amplitude is at the greatest distance from rest position.

Traveling Wave

A repeating pattern moving uninterrupted through a medium.

Wave Interaction

When a wave interacts with another medium, its properties may change.

Period

Time to complete a cycle of vibration.