Electromagnetic Waves

What are EM waves?

Waves that travel by oscillation of the electric and magnetic field. Electromagnetic waves are transverse waves. They do not need a particle medium to travel through.

An electromagnetic wave has a frequency of 8×1019Hz8 ×1019 Hz.

What class in the electromagnetic spectrum would this wave belong to?

X rays

What is a plane polarised wave

A transverse wave in which the oscillations are limited to only one plane

When two polarising filters are aligned perpendicular to each other…

…none of the light that passes through the first filter, passes through the second.

When two polarising filters are aligned parallel to each other…

…, all of the light that passes through the first filter, passes through the second.

What is refraction?

When a wave changes direction as it enters a new medium, due to a change in the speed of travel

What is the critical angle?

The angle of incidence at the boundary between two media that will produce an angle of refraction of 90 degrees

What is total internal reflection?

The reflection of all light back into the original medium when hitting a boundary between two media; the original medium will have a higher refractive index and the incidence angle at the boundary must be greater than the critical angle.

What is dispersion?

this is when some wavelengths of light refract more easily than others.