Superposition is the ability of waves to superimpose
Superposition is the ability of waves to superimpose (add displacements & energy) as they move through each other. Constructive interference. Approaching Overlapping Receding
Destructive interference. Approaching Overlapping Receding
Combining waves of the same f What happens when two waves are present at the same place at the same time?
The Principle of Interference / Superpositioning For waves: The resulting wave = the sum of the individual waves Constructively Destructive This applies to all waves: water, light, sound, etc.
Interference: What happens when two waves pass through the same region? When two crests overlap it is called constructive interference. The resultant displacement is larger then the individual ones. When a crest and a trough interfere, it is called destructive interference. The resultant displacement is smaller.
Phase • Two quantities are in phase if they are simultaneously increasing or decreasing, eg V & I are in phase in an AC circuit Waves in phase
2 waves out of phase by ½ a cycle or 180 o. Crest of one wave coincide with the trough of the other wave.
• If there is a period of time where one quantity is increasing while the other is decreasing they are out of phase. • The two quantities need to have the same frequency (f) but not necessarily the same amplitude to stay in phase. Waves out of phase by 90 o or a ¼ cycle
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Beats is a regular pulsing of the loudness of a sound which is heard when two sources produce sounds of slightly different frequency. fbeat = f 1 – f 2 For example, when a 552 Hz and a 556 Hz tone are played simultaneously, we hear 556 -552, or 4 beats per second. The beat frequency is 4 Hz. Uses ~ Piano Tuning
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