Waves

Wave

A disturbance of movement that moves energy through matter or space

Medium

The matter (solid, liquid, gas) that mechanical waves travel through

Crest

The highest point in a transverse wave. Above rest position

Trough

The lowest point in a transverse wave. Below rest position.

Wavelength of Transverse wave

A measurement of the distance between two crests or two troughs.

2 major categories of waves

Mechanical (need a medium) and electromagnetic (do not need a medium).

2 types of mechanical waves

Transverse waves and compressional waves

Amplitude

How much energy a wave has.

How to measure amplitude

Finding the distance from the resting point to the crest of a transverse wave.

Amplitude of sound wave

The volume.

Frequency

How many waves pass a certain point in a second

How frequency is measured

Measured in Hertz/Hz

Frequency of sound wave

Pitch

Electromagnetic waves

DO NOT need a medium to travel through in order to transfer energy/ They can travel through a vacuum (space). Examples are microwaves, x-rays, ultraviolet light, visible light.

Electromagnetic wave examples

Light waves, radio, x-rays, UV rays, and microwaves.

Mechanical waves

Waves that NEED a medium to travel through, transverse and compressional.

Two types of mechanical waves

Transverse and compressional.

Transverse Wave

Energy in the medium moves back and forth at right angles to the direction the wave travels.

Longitudinal wave

Also known as compressional waves. The energy moves back and forth in the same direction that the wave travels.

Characteristics of TRANSVERSE WAVES

A: Amplitude, B: Wavelength, C: Trough, D: Crest, E: Point of rest/equilibrium.

If wavelength increases

The frequency decreases

Characteristics of compressional

A: wavelength, B:Amplitude, C:Compression, D:Rarefaction, E: Compresion

Compression

An area on the wave where the medium becomes more dense (squeezed tightly)

Rarefraction

An area on the wave where the medium is less dense.

Wavelength of compressional waves

Distance from one point of a wave to the nearest point just like it (from compression to compression or from rarefaction to rarefaction).

Reflection

The process by which a wave hits an object and BOUNCES off of it.

Absorption

When a wave hits a material and it is not reflected back (instead it gets sucked in).

Transmission

“To go through”

Amplitude

in a compressional wave, the amplitude depends on the density of the medium in the compressions and rarefactions.  (Very high amplitude compressional waves have very dense compressions and very low density rarefactions)

***the greater the amplitude, the more energy the wave carries 

***if you increase the AMPLITUDE of a compressional wave, the VOLUME gets louder