combining waves Flashcards
What is superposition
when two waves of the same type overlap and interact. The displacement of the medium, where the waves overlap, is the vector sum of the two wave displacements
What is inteference
name given to the superposition of waves from two coherent sources of waves. Interference is constructive if waves are in phase, or destructive if waves are in anti-phase.
when are two waves coherent
when they have a fixed phase difference and have the same frequency
What does Youngs double slit experiment demonstrate
Demonstrates interference between coherent light sources, thus showing the wave nature of light
How does the double slit experiment take place
The experiment uses two coherent sources of light, produced from a single source of light, which then pass through two very narrow, parallel slits. The light diffracts through the slits, producing an inteference pattern on a screen.
Why does interference occur during the double slit experiment
due to the overlapping waves and they then superpose in a stable pattern
What is a stationary wave
Is a wave formed by the superposition of two progressive waves of the same frequency and amplitude travelling in opposite directions.
How are stationary waves created
created when two progressive waves of the same frequency and amplitude moving in opposite directions superpose. When waves reflect off a rigid boundary, the reflected waves
What occurs on a stationary wave in terms of nodes
At the node there is total destructive interference, whereas at an anti-node there is constructive inteference
What is constructive inteference
When two waves meet, if their displacements are in the same direction, they combine to give a bigger displacement
What is destructive interference
If a wave with positive displacement meets a wave with negative displacement, they will cancel each other out.
