1. Types of waves
1.1. Transverse
1.1.1. oscillation perpendicular to direction of travel
1.1.2. examples:
1.1.2.1. light waves
1.1.2.2. water waves
1.1.3. only some are mechnical.
1.2. Longitudinal
1.2.1. Oscillations in the direction of travel
1.2.2. compressions and rarefactions
1.2.3. examples:
1.2.3.1. sound waves
1.2.3.2. Tsunami wave
1.2.4. All longitudinal waves are mechanical
1.2.5. diagram
1.3. Mechanical
1.3.1. Transmitted through medium, vibrating particles
1.4. Electromagnetic
1.4.1. Do not need medium, oscillation of magnetic and electric field perpendicular to each other
1.4.2. diagram
1.4.3. Light
2. descrtiptive terms
2.1. speed
2.1.1. unit: m/s
2.1.2. formula: Frequency x wavelength
2.2. frequency
2.2.1. Number of waves passing any point per second
2.2.1.1. unit: Hz
2.2.2. Also: pitch
2.2.2.1. octave: frequency doubles
2.3. Wavelength
2.3.1. dist between any point of a wave and the equivalent point on the next
2.4. amplitude
2.4.1. max dist fr rest position
2.4.2. Loudness
2.4.3. Double amplitude = 4x energy
2.5. Period
2.5.1. time for one oscillation
2.5.1.1. formula: 1/frequency
2.5.1.2. unit: s
3. Wave effects
3.1. Reflection
3.1.1. incident angle = reflected angle
3.1.2. diagram
3.1.3. When a vertical surface is put in the path of a wave
3.1.4. Frequency, wavelength and speed same. angle iº = rº
3.2. Refraction
3.2.1. When the wave changes speed and direction (NOT frequency)
3.2.2. Diagram
3.2.3. Frequency UNCHANGED. Speed, direction and wavelength changes
3.3. Diffraction
3.3.1. When the waves bend around the sides of an obstacle, or spread around as they pass through a gap
3.3.2. diagram
3.3.3. speed, frequency and wavelength stays the same. AMPLITUDE decreases
4. Definition
4.1. A disturbance travelling through space or matter transferring energy from one place to another
5. Sound waves
5.1. longitudinal, need medium to travel through
5.2. Oscilloscope
5.3. Echo
5.4. Speed of sound
5.4.1. Factors:
5.4.1.1. Temperature
5.4.1.1.1. warmer = faster
5.4.1.2. material
5.4.1.3. NOT AFFECTED BY pressure
5.4.2. 330m/s in air at 0ºc
5.5. Other waves
5.5.1. Ultrasound
5.5.2. Echo-sounding
6. Light waves
6.1. a form of radiation, transfers energy
6.2. travels in straight lines
6.3. characteristics
6.3.1. Wavelength, colour
6.4. Reflection in a plane mirror
6.4.1. Laws of Reflection
6.4.1.1. 1. Angle of incidence equal to angle of reflection
6.4.1.2. 2. Incident ray, reflected ray and normal all lie in the same place
6.4.2. Laterally inverted
6.4.3. Same size
6.4.4. same distance from the mirror surface
6.5. Effects
6.5.1. refraction
6.5.1.1. when light travels through mediums of different densities
6.5.1.2. real and apparent depth
6.5.1.3. refractive index
6.5.1.3.1. Speed of light in vacuum/speed of light in medium
6.5.1.3.2. sin(i)/sin(r) = refractive index (n)
6.5.1.4. Prism
6.5.1.4.1. Different wavelengths have different degrees of refraction
6.5.1.4.2. Spectrum
6.5.2. Total internal refraction
6.5.2.1. angle of incidence greater than critical angle
6.5.2.1.1. diff materials have diff critical angles
6.5.2.1.2. sin c = 1/n, where n = refractive index
6.5.2.2. optical fibres
6.5.2.2.1. sending information
6.6. Lenses
6.6.1. Types
6.6.1.1. Concave
6.6.1.2. Convex
6.6.2. properties
6.6.2.1. principal focus
6.6.2.2. principal axis
6.6.2.3. focal length
6.7. Electromagnetic spectrum
6.7.1. radio waves
6.7.1.1. Long wave, medium wave, short wave, VHF, UHF, microwaves
6.7.2. infrared
6.7.3. visible light spectrum
6.7.4. ultraviolet
6.7.5. X-ray
6.7.6. gamma ray