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Light as a wave
· describe light as a transverse electromagnetic wave which is produced by the acceleration of charges, which in turn produces changing electric fields and associated changing magnetic fields · identify that all electromagnetic waves travel at the same speed, c, in a vacuum · explain the formation of a standing wave resulting from the superposition of a travelling wave and its reflection · analyse the formation of standing waves (only those with nodes at both ends is required) · investigate and explain theoretically and practically diffraction as the directional spread of various frequencies with reference to different gap width or obstacle size, including the qualitative effect of changing the ratio, and apply this to limitations of imaging using electromagnetic waves · explain the results of Young’s double slit experiment with reference to: - evidence for the wave-like nature of light - constructive and destructive interference of coherent waves in terms of path differences: nλ and (n+1/2)λ respectively, where n = 0,1, 2,… - effect of wavelength, distance of screen and slit separation on interference patterns: x=λL/d when L>>d |
