Terms : Hide Images
| 61572747 | Electromagnetic Wave | Consists of the oscillation of electric & magnetic fields, transverse waves | |
| 61572748 | Transverse Waves | Direction of oscillation is at 90° to the direction the wave energy is travelling | |
| 61572749 | Longitudinal Waves | Direction of oscillation is in the same direction the wave energy is travelling | |
| 61572751 | Time Period | The time taken to complete one complete oscillation | |
| 61572753 | Frequency | Number of oscillations / time taken | |
| 61572754 | Time Period = | 1 / Frequency | |
| 61572755 | Wave Length λ | The distance between points at the same phase on neighbouring wave cycles | |
| 61572756 | V = | fλ | |
| 61572757 | When waves are incident on a boundary between two different media | Some of the wave energy is reflected and some is transmitted | |
| 61572758 | Refraction | The change in wave velocity which results when waves travel from one medium to another which usuallly results in a change in direction | |
| 61572759 | Diffraction | The spreading out of wave energy as waves move through a narrow gap or past a narrow obstacle | |
| 61572760 | For significant diffraction to occur | The gap must be of similar size to the wavelength | |
| 61572761 | The Principle of Superposition | The resulting disturbance at each instant is the vector sum of the individual wave disturbances at that point | |
| 61572762 | Constructive Interference | Occurs when waves that are in phase are superposed | |
| 61572763 | Destructive Interference | Occurs when waves that are π out of phase are superposed | |
| 61572764 | Coherent Waves | Waves with a constant phase difference | |
| 61572765 | Coherent Wave Sources | Produce waves with a constant path difference | |
| 61572766 | Path Difference | The difference between, the distance from the source to a point, for two waves | |
| 61572767 | Intensity = | Power / Area | |
| 61572768 | Intensity α | Amplitude² | |
| 61572770 | Monochromatic Light | Single wave length light | |
| 61572771 | Coherent Light | Constant uninterupted flow of light | |
| 61572772 | Laser light produces | Continous coherent waves | |
| 61572773 | Diffraction Grating consists of | a large number of evenly spaced slits | |
| 61572774 | Path Difference: | dsinø = nλ (where d is source seperation) | |
| 61572775 | As the number of slits increases | the dark fringes expand and the bright fringes are more defined | |
| 61572776 | Node | Point on a standing wave with minimum amplitude caused by destructive interference | |
| 61572777 | Anti-Node | Point on a standing wave with maximum amplitude caused by constructive interference | |
| 61572778 | Standing waves occur when | Progressive waves are reflected by two boundaries so that the wave energy is contained within a fixed region. Two coherent waves travelling in opposite directions are superposed to produce a wave interference pattern | |
| 61572780 | When light is reflected | it is partially polarised | |
| 61572781 | Plane of polarisation | the plane in which oscillation occurs | |
| 61655843 | rest line | the line from which the vibration is measured; matter at rest | |
| 61655844 | vibration | a repeated back and forth motion that creates a wave | |
| 61655845 | compression | when the particles are squeezed together | |
| 61655846 | wave | a travelling disturbance that moves energy, not matter | |
| 61655847 | crest | the highest point of wave. | |
| 61655849 | amplitude | the distance from the rest position to the crest or trough | |
| 61655850 | mechanical wave | a wave that requires a medium through which to travel | |
| 61655851 | medium | matter (solid, liquid, gas) through which a wave travels | |
| 61655852 | hertz | the unit of frequency equal to cycle per second; Hz | |
| 61655853 | seismic wave | A vibration that travels through Earth carrying the energy released during an earthquake | |
| 61655854 | absorb | to take in | |
| 61655855 | transmit | to send on, pass along, send out | |
| 61655856 | trough | lowest point of the wave | |
| 61655857 | reflect | bouncing of a wave or ray off a surface, changing its direction | |
| 61655858 | constructive interference | Addition of two waves when the crest of one overlaps the crest of another, so that their individual effects add together. The result is a wave of increased amplitude. | |
| 61655859 | destructive interference | Addition of two waves when the crest of one overlaps the trough of another, so that their individual effects cancel each other. The result is a wave of decreased amplitude. | |
| 61655860 | rarefaction | a part in a longitudinal wave where the particles are spread apart |
