4. Superposition and Interference Flashcards
What does superposition happen?
When two or more waves pass through each other
What is the principle of superposition?
When two or more waves cross, the resultant displacement equals the vector sum of the individual displacements
What can the superposition of two or more waves result in?
Interference
Name the 2 types of interference
- Constructive
2. Destructive
When does constructive interference happen?
When two waves meet, if their displacements are in the same direction, the displacements combine to give a bigger displacement
Name 2 examples of when constructive interference occurs?
- Peak + peak
2. Trough + trough
When does destructive interference happen?
If a wave with a positive displacement meets a wave with a negative displacement, the displacements combine to give a smaller displacement
Name an example of when destructive interference occurs?
Peak + trough
What is the interference called when a peak and a trough meet?
Total destructive interference
When are two points in phase with each other?
When they are both at the same point in the cycle (i.e. if the phase difference is 0 or a multiple of 360 degrees)
What conditions need to be met for waves to be in phase with each other?
- Same frequency
2. Same wavelength
What condition does not matter for waves to be in phase with each other?
Amplitude
How do you ensure that waves are in phase with each other?
The waves come from the same oscillator
When are two points exactly out of phase?
They are an odd integer of half-cycles apart (1 half-cycle, 3 half-cycles etc…)
