Light Waves Module 2 Notes

Wave

A transmission of energy and information without the physical transport of material.

Photon

A particle of electromagnetic radiation that carries energy.

Speed of light (c)

The speed of light is approximately 300,000 km/s or 3 x 10^5.

Crest

The highest point of a wave.

Trough

The lowest point of a wave.

Amplitude

Maximum displacement of the wave from its undisturbed state; indicates the height of the wave.

Wavelength

The distance between successive crests or troughs; shorter wavelengths correspond to higher energy.

Wave period

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

Frequency

How many waves pass in a second, measured in hertz; higher frequency means more energy.

Wave speed

Calculated as frequency multiplied by wavelength.

Electromagnetic waves

Waves that do not require a medium to travel and include gamma rays, x-rays, ultraviolet light, visible light, infrared, radio waves, and microwaves.

Opacity

A measure of how much radiation is blocked; higher opacity means more radiation is blocked.

Blackbody radiation

Radiation emitted by objects at everyday temperatures, typically in the infrared spectrum.

Diffraction

The bending of a wave around an obstacle.

Interference

The sum of two waves which can be either larger or smaller than the original wave, leading to constructive or destructive interference.

Kelvin scale

A temperature scale where all thermal motion stops at 0 degrees K, water freezes at 273 degrees K, and boils at 373 degrees K.