Practice question · True or false
Two identical waves meeting exactly out of phase cancel, which means their energy has been destroyed.
Hints
- Where would the energy have gone?
- Cancelling here implies reinforcement elsewhere.
Show the answer
False
Why
False. Energy is conserved: destructive interference at one point is always accompanied by constructive interference elsewhere, and the total over the whole pattern is unchanged. That is why an interference pattern has bright fringes exactly where the dark ones are missing their energy.
Practise Oscillations and Waves
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