Oscillations (vibrations) waves physics

Waves and their types.

Oscillation defintion

Vibration of particles around a mean position

Amplitude (A) defintion

An oscillating object’s maximum displacement

Period (T) definition

The time taken to complete one oscillation

Waves definition

A disturbance that transfers energy through a medium or space by having matter vibrate and move energy along each other when they make contact

What is a pulse wave

When a single wavelength is produced

Classification of waves

Mechanical or elctromagnetic

Mechanical wave

waves that require a medium to transmit energy

e.g. Water waves, sound waves and waves in strings and springs are all mechanical waves.

Electromagnetic waves

waves that do not require a medium to transmit energy

e.g. Visible light, gamma rays and radio waves are all electromagnetic waves

Transverse waves

Waves where the particles in the medium (or the fields in an electromagnetic wave) oscillate at right angles to the direction of wave travel. Can be electromagnetic or mechanical.

Crest defintion

an area of maximum positive displacement (x = +A) in a transverse wave.

Trough definition

an area of maximum negative displacement (x = -A) in a transverse wave

How do particles oscillate for transverse waves

Individual particles oscillate at right angles to the direction of wave travel

Longitudinal waves

waves where the particles in the medium oscillate back and forward in the same plane as the wave travels. e.g. Sound waves and compression waves in springs are examples of longitudinal waves. Don’t have crest and troughts

How do particles osciallte in longitudinal waves

As the backwards and forwards oscillations propagate through the medium, particles bunch together in some regions and spread apart in others.

Compression

An area where particles of the medium are bunched together in a longitudinal wave

Rarefactors

An area where particles in the medium are spread apart in a longitudinal wave.

What wave is sound waves

Sound waves are a type of longitudinal wave

How are sound waves produced

when a vibrating object causes air molecules to oscillate

Another name for sound waves

Sound waves are also called pressure waves as the compressions are areas of high pressure and the rarefactions are areas of low pressure.

What happens to sound waves when they are plotted on a graph

Become transverse, compression become crests and rarefactions become troughs