Understanding Amplitude In Simple Harmonic Motion (SMH)

Simple harmonic motion is an oscillatory motion. It is a motion in which a particle moves to and fro repeatedly on a mean position in the presence of restoring force. The mean position is the middle position where the displacement is zero. All the simple harmonic motions are oscillatory. The study of the simple harmonic motion is very important and useful and is used to understand the sound waves and light waves. In Simple harmonic motion, the restoring force is directly proportional to the displacement of the body. The direction of restoring force is always towards the mean position. 

Amplitude Definition

What is amplitude?

The maximum displacement of a wave from its mean position to either side defines amplitude. 

For a transverse wave, such as a string, the plucked amplitude is measured by the maximum displacement of any point on the plucked string from the rest position of the string. For longitudinal waves, the sound wave amplitude is measured by the maximum displacement of the particle from the position of equilibrium. When the wave’s amplitude decreases because of the energy lost, it is known as damped. 

The unit of amplitude relies on the type of wave. For waves on a string or water, the amplitude is displacement.  

The amplitude of a wave

Wave amplitude is the maximum displacement of the particle of the medium that moves from its resting position when a wave passes through. Wave amplitude is a form of energy produced by the vibration of the body. Wave requires a medium for its propagation. Sound can not propagate in the vacuum as there will be no particle to transfer the wave. 

Small waves of water, sound travelling in the air and vibrations of objects are some of the examples of waves that are encountered by us every day. If we put a stick in the still water of a pond, some waves will form on the surface, which is a good example of the amplitude of a wave. 

Electromagnetic waves like radio waves, x-ray waves, and microwaves are some of the waves which do not require a medium for propagation. We can not see these waves, but they exist around us in the form of products we use in everyday life. 

Every wave has an amplitude. The wave amplitude is referred to the length and the width of the wave. The distance, length and width of waves like sound waves as they move or vibrate is known as the amplitude. 

Properties of waves

There are many properties of waves that scientists have described. Some of them are:- 

Wavelength

The wavelength of the wave is the distance between two successive waves. The distance between back to back cycles is also called the wavelength of waves. This can be calculated by taking the distance between the two crests or the two troughs of a wave. Wavelength is usually denoted by lambda (λ)

Frequency and period

The frequency of a wave is the number of waves passing through a fixed juncture in a given time. The SI unit of frequency is known as Hertz(Hz). The frequency is also represented as “f”. A high-frequency wave has more energy, and a known frequency wave has less energy. 

The period is the time taken for a wave cycle to complete or the time between the crests. The period can be represented as ” T” 

Frequency and period are reciprocally each other and are also denoted by the formula:-    

                         T= 1/f 

Speed or the velocity of a wave. 

In a pond where there is still water, if you put a stick into it, there will be some disturbance in the pond, which is known as the wave if we observe the waves if they travel from one place to another in a given interval of time. The speed of a wave refers to how fast a wave can travel, and it is expressed as the distance covered per time of the travel. If the waves in the pound cover 20 meters in 10 seconds, then the speed of the wave is 2.0m/s. 

The velocity of the wave indicates both the speed and the direction of the wave. The velocity of the wave is denoted as “v”.

Conclusion 

Simple harmonic motion is a periodic motion in which particles move to and fro along a straight line. SMH is an oscillatory motion. When a string is plucked in a transverse wave, the amplitude is measured by the maximum displacement of any point on the plucked string. For a longitudinal wave, the amplitude is measured by the maximum displacement of the article from the position of equilibrium. The amplitude of the wave is the maximum displacement of the particle of the medium that moves from its resting position when a wave is passing. Wave amplitude is a form of energy that is produced by the vibrations of the body.