Frequency of the wave is 2 per second
Explanation:
- Frequency is the number of times waves pass at a particular point of time. Here, given time period = 3 s and number of waves that pass in 3 seconds = 6. Find the frequency of the wave per second.
- Frequency is given by the formula
f = 1/T, where f is the frequency and T is the time period
- For 3 seconds, frequency is 6
3 seconds ⇒ 6 waves
⇒ 1 second = 6/3 = 2 waves per second
The answer is A, an appeal of association
The phenomenon which is responsible for this effect is called diffraction.
Diffraction is the ability of a wave to propagate when it meets an obstacle or a slit. When the wave encounters the obstacle or the slit, it 'bends' around it and it continues propagate beyond it. A classical example of this phenomenon is when a sound wave propagates through a wall where there is a small aperture (as in the example of this problem)