C2/C3 waves physics

What is frequency? (Hz) Is it fixed?

The number of complete wave cycles that pass a fixed point in 1 second

OFTEN fixed because it is set by the material/source

Mechanical vs electromagnetic waves:

Mechanical → oscillations of MASSES (water waves, sound waves, waves on strings/ropes) CANNOT GO THRU VACUUM

Electromagnetic waves → oscillations of ELECTRIC and MAGNETIC fields (light, E-M radiation) CAN GO THRU VACUUM

All waves transfer ENERGY, not _____

MATTER

Transverse vs Longitudinal waves:

Transverse → a wave that oscillates PERPENDICULAR to the direction of travel / energy transfer

Longitudinal → a wave that oscillates PARALLEL to direction of travel / energy transfer

Wavelength? (Y upside down)

Shortest distance between two troughs or peaks (transverse) or compressions and rarefactions (Longitudinal)

OR between two points moving in phase!!

Amplitude?

the maximum displacement of the medium from its equilibrium position

Time period?

the time for one oscillation of a particle within the medium

OR the time it takes for one complete wave to pass a particular point (unit: second)

Frequency? Hz

the number of oscillations per SECOND of a particle within the medium

OR the number of waves to pass a particular point in one second

Wave pulse?

A short (duration) oscillating disturbance passing through a medium

What is the right hand rule for electromagnetic waves?

Propagation = direction of travel / movement

What waves follow ‘c’ as their speed when in air/vacuum?

LIGHT mainly, electromagnetic waves like radio/visible all follow this same speed too as they’re all from the same wave / spectrum

Reflection vs Refraction?

Refraction → the change in direction of a wave that occurs when it changes speed upon entering a different medium.

Reflection → the wave cannot pass through the boundary into the next medium so it BOUNCES BACK

When do waves refract TOWARDS the normal?

• Waves refract towards the normal when entering a medium where they travel more slowly

Diffraction Vs Interference

Interference → the overlapping of waves from two or more separate sources

Diffraction → the bending / spreading of a wave as it passes around an obstacle or through a single opening

Wavefront?

A line joining neighboring points moving in phase with each other

What is transmission?

The process in which waves are able to travel through a medium (e.g. sounds waves can be transmitted through water)

What is scattering?

Waves may also be randomly misdirected by interactions with irregularities in a medium

(e.g. bathroom window)

How is intensity and amplitude linked?

Intensity <>< amplitude²