Waves

WAVES

Definition: Waves are rhythmic disturbances that carry energy without carrying matter.

Mechanical Waves

Definition: Need matter (or medium) to transfer energy.

Types of medium: Air; water; particles; strings; solids; liquids; gases

Electromagnetic Waves

Definition: Need matter (or medium) to transfer energy.

Transverse Waves

Definition: Energy causes the matter in the medium to move up and down or back and forth at right angles to the direction the wave travels.

Example: waves in water

Parts:

- The crest is the highest point on a wave.

- The trough is the valley between two waves, is the lowest point.

- The wavelength is the horizontal distance, either between the crests or troughs of two consecutive waves.

- The amplitude is the distance from the undisturbed level to the trough or crest.

Definition: Transverse waves that DO NOT NEED matter

(medium) to transfer energy.

Examples: radiation, TV & radio waves, X-rays, microwaves, lasers, energy from the sun, visible light.

Parts:

Electromagnetic waves are considered transverse waves because they have similar characteristics; therefore, they have the same parts.

Compressional Waves

Definition: A mechanical wave in which matter in the medium moves forward and backward along the same direction that the wave travels.

Example: Sound waves

Parts:

- The compression is the part of the compressional wave where the particles are crowded together.

- The rarefaction is the part of the compressional wave where the particles are spread apart.

- The wavelength is the distance from compression to compression or rarefaction to rarefaction in a compressional wave.