Question

P is a particle in the path of sound waves progressing in the OX direction. When the fork is moved towards P, what change will occur in the amplitude of vibration of P?

Answer 1

In this question we will use the concept of amplitude by fork. Also we will see the basic concept of wave and its propagation in any medium. Also, we will learn about basic physical terms like amplitude, frequency and its unit.

Complete step by step solution:
Here, the amplitude produced by the fork does not depend on the movement of the fork i.e., independent of the movement of the fork. So, even though the fork is moved toward P, the amplitude remains the same.
We also know that amplitude can be defined as the maximum displacement or distance moved by a point on a vibrating body or wave when measured from its equilibrium position.

Additional information:
Waves involve the transfer of energy without the transfer of the matter. So, it can be said that waves can be described as a disturbance that travels through a medium, transporting energy from one location to another location without transfer of matter. Here we have a graph showing the propagation of a wave.

Further, the frequency is defined as the number of waves that pass a fixed point in unit time. It can also be defined as the number of cycles or vibrations undergone during one unit of time.
Two waves are said to be coherent if they are moving with the same frequency and have constant phase difference.
The summation or adding or subtraction of all the waves travelling in a particular medium, gives us the superposition of waves. If the direction or amplitude of the waves are opposite then the superposition of waves is calculated by subtracting the waves, whereas if the two waves are travelling in the same direction or have the same amplitude the resultant is given by adding up the two or more waves.
The S.I unit of frequency is Hertz or Hz and the unit of wavelength is meter or m. Furthermore we also know the S.I unit of time which is given by second or s.
Phase of a wave specifies the location of a point within a wave cycle of a repetitive waveform. Generally, the phase differences between two or more sound waves are important. Rather than the actual phases of the signals. When two sound waves combine, like- the difference between the phases of the two waves is important in determining the resulting waveform.

Note:
We should note that mathematically intensity can be expressed as the square of the amplitude. The phase of the wave can be positive or negative depending on its direction of propagation. A sine wave starts from zero, whereas the cosine wave starts from one. A wave which has the same amplitude but opposite orientation will cancel out each other and thereby give zero output.