Difference Between Mechanical Waves and Electromagnetic Waves

Main Difference

The main difference between mechanical waves and electromagnetic waves is that mechanical waves require a medium (air or water) for their propagation, whereas electromagnetic waves do not require a medium for their propagation (can travel through space).

Mechanical Waves vs. Electromagnetic Waves

Mechanical waves must travel through a medium, while electromagnetic waves don’t need to travel through a medium. Mechanical waves are usually not made from anything because they are created by a disturbance or vibration in a medium like in matter like plasma, liquid, solid, and gas, whereas electromagnetic waves are created by something like electromagnetic energy and it is the most important energy in the universe for the propagation. Mechanical waves are usually formed by wave amplitude and not caused by wave frequency; on the other hand, electromagnetic waves are formed by vibration of the charged particles.

Mechanical waves are generally deliberated as a periodic disturbance; on the contrary, electromagnetic waves are known as just a disturbance of electric charges. Example of mechanical waves is the ripples that are formed in the in a pool of water when a stone is thrown in the middle of the pool; on the flip side, examples of electromagnetic waves are radio signals and light. Speed of mechanical waves usually determined by the elastic properties of the source; on the flip side, the speed of electromagnetic waves is generally inversely proportional to the refractive index of the source.

Mechanical waves move slower than electromagnetic waves with a speed of sound in air is 332 m/s; on the other hand, electromagnetic waves generally travel considerably quicker than the mechanical waves with the speed of light in a vacuum is 3 x l0 8 m/s. The types of mechanical waves can be both longitudinal waves and transverse waves, but an electromagnetic wave could only be a transverse wave. Mechanical waves are produced because of vibrations of the particles in the medium; on the flip side, electromagnetic waves are produced by the fluctuating electric and magnetic fields. Magnetic fields usually have low frequency and large wavelength; on the contrary, electromagnetic waves generally have high frequency and low wavelength.

Comparison Chart

Mechanical WavesElectromagnetic Waves
A mechanical wave is considered as a type of wave which is an undulation of substance and hence transmits energy over a source.Electromagnetic waves are the waves that do not require a medium for their propagation and can travel through space.
Medium Requirement
Requires a medium for the propagationDo not require a medium for the propagation
Created By
Created by a disturbance or vibration in a medium like in matter like plasma, liquid, solid, and gasCreated by something like electromagnetic energy
Cause of Formation
Usually formed by wave amplitude and not caused by wave frequencyFormed by the vibration of the charged particles
Deliberated As
Deliberated as a periodic disturbanceKnown as just a disturbance of charged particles
Speed of Waves
Usually determined by the elastic properties of the sourceGenerally inversely proportional to the refractive index of the source
Rate of Speed
Move slower than electromagnetic waves with a speed of sound in air is 332 m/sTravel considerably quicker than the mechanical waves with the speed of light in a vacuum is 3 x l0 8 m/ s.
Types of Waves
Both longitudinal and transverse wavesA transverse wave
Produced Because Of
Produced because of vibrations of the particles in the mediumProduced by the fluctuating electric and magnetic fields
Consist Of
Usually, have low frequency and large wavelengthGenerally, have high frequency and a low wavelength
Examples
The ripples that are formed in the in a pool of water when a stone is thrown in the middle of the poolRadio signals and light

What are Mechanical Waves?

The waves that must need a medium for their propagation is known as mechanical waves. Though, the medium doesn’t need to be a gas or a liquid medium because mechanical waves could transmit through solids too. Mechanical waves such as sound create compression when propagating from a medium, by a liquid, solid, gas, or plasma medium, disturbing the molecules of substances. For instance, when sound waves passing through the air medium causing displacement of air molecules, result in the vibration and collision with other molecules present in the air at a particular frequency when the wave propagates through the medium.

The molecules of air jump back in their original place; and for every force, there is the formation of an equal and opposite force in the medium. As a result, the molecules vibrate to and fro analogous to the source. It is wave propagation generally true for gasses and liquids, but usually not for a thicker substance. The types of mechanical waves can be both longitudinal and transverse waves.

Both transverse and longitudinal waves generally in surface waves mingling in a single medium. Mechanical waves usually do the transportation of energy. This transported energy travels in the equivalent direction as the in the direction of the wave. Any wave, either mechanical or electromagnetic consist of definite energy.

Mechanical waves could only be formed in media that contains inertia and elasticity. A mechanical wave usually involves a primary energy contribution. When once this primary energy is added in the propagation of the wave, the wave then travels by the medium until all of the wave energy is shifted. Example of mechanical waves is that the mechanical waves could be seen in the ripples that are formed in the in a pool of water when a stone is thrown in the middle of the pool.

Types

  • Transverse Waves: The wave moves at right angles to the medium direction such as light.
  • Longitudinal Waves: The wave moves equivalent to the medium direction — for instance, sound.
  • Surface Waves: The surface waves propagate laterally on the outward of the medium or between the two mediums, for example, the surface waves present in an ocean, or a pool, lake, or in any further kind of water body.

What are Electromagnetic Waves?

The wave that does not require a medium for its propagation and oscillation between mediums is known as electromagnetic waves. Electromagnetic waves could be light waves, but they usually don’t just consist of the visible light that we could see. Electromagnetic waves generally transmit energy advancing but never use a medium for its propagation that’s why light can easily reach Earth from the medium Sun.

If electromagnetic waves somehow were mechanical, then there would be possibly no heat, light, or life on Earth. Electromagnetic waves are created by something like electromagnetic energy, and it is the most important energy in the universe for the propagation. Various examples of electromagnetic waves are radio and signal light.

Types

  • Radio Waves: Instant Communication
  • Microwaves: Data and Heat
  • Infrared Waves: Invisible Heat
  • Visible Light: Rays
  • Ultraviolet Waves: Energetic Light
  • X-Rays: Penetrating Radiation
  • Gamma Rays: Nuclear Energy

Key Differences

  1. Mechanical waves usually propagate through a substance, while electromagnetic waves don’t require to propagate through a medium.
  2. Mechanical waves are not produced by wave frequency but are formed by wave amplitude; on the other hand, when vibration occurs on the charged particles, the electromagnetic waves are formed.
  3. Mechanical waves are generally deliberated as a periodic disturbance; on the contrary, electromagnetic waves are known as just a disturbance.
  4. Mechanical waves are only created by vibration or a disturbance in a medium such as in plasma, liquid, solid, and gas, whereas electromagnetic waves are the most vital energy in the universe for the propagation because they are created by electromagnetic energy.
  5. The elastic properties of the source are used to determine the speed of mechanical waves; on the flip side, the speed of electromagnetic waves is inversely proportional to the refractive index of the source.
  6. Mechanical waves propagate slower with a speed of sound in air 332 m/s; on the other hand, electromagnetic waves generally move significantly quicker than the mechanical waves with the speed of light in a vacuum 3 x l0 8 m/ s.
  7. Both longitudinal and transverse waves could be the types of mechanical waves, but an electromagnetic wave could only be a transverse wave.
  8. Because of vibrations of the particles in the medium, it will also lead to the formation of mechanical waves; on the flip side, the fluctuation present in electric and magnetic fields result in the production of electromagnetic waves.
  9. Magnetic fields usually contain large wavelength and low frequency; on the contrary, electromagnetic waves contain low wavelength and high frequency.
  10. Example of mechanical waves is that when a stone is thrown in the middle of the pool, the ripples that are formed in the in a pool of water will generate mechanical waves; on the flip side, examples of electromagnetic waves are radio signals and light.

Conclusion

Above discussion concludes that the mechanical waves are usually formed by wave amplitude and not caused by wave frequency and usually require a medium for their propagation; on the other hand, electromagnetic waves are formed by vibration of the charged particles and do not require a medium for its propagation.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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