Electromagnetic Waves: Propagation and Characteristics
by Yuvi K - December 18, 2023
What are Electromagnetic Waves?
Electromagnetic waves (विमान तारागणकी)are waves that travel through the air or a vacuum at the speed of light. They are composed of oscillating electric and magnetic fields at right angles to each other. These waves are very powerful and are capable of transmitting energy over long distances. They are used to send radio signals, heat up microwaves, and other uses.
Propagation of Electromagnetic Waves
Electromagnetic waves propagate through space in a straight line. They travel at the speed of light and are not affected by gravity, air density, or other environmental influences. The energy of the radiation is absorbed by any matter that it comes in contact with but it is not absorbed by a vacuum. The frequency of the waves determines the amount of energy that is absorbed.
Types of Electromagnetic Waves
There are seven different types of electromagnetic (चुंबकीय) waves which are named after their wavelengths. They are:
| Type of Wave | Wavelength | Frequency | Application |
|---|---|---|---|
| Radio Waves | 1 meter – 1000 kilometers | 3 Hz – 300GHz | Radio transmissions, cell phones |
| Microwaves | 1mm – 1 meter | 300GHz – 300 THz (300 million GHz) | Wi-Fi, radar, medical diagnostics, food preparation |
| Infrared | 750nm – 1mm | 300 THz – 400 THz (400 million GHz) | Thermography, TV remote control |
| Visible Light | 400nm – 750nm | 400 THz – 790 THz (790 million GHz) | Photography, videos, lasers |
| Ultraviolet | 10nm – 400nm | 790 THz – 3 PHz (3 billion GHz) | Laboratory and biological research |
| X-rays | 0.01nm – 10nm | 3 PHz – 30 PHz (30 billion GHz) | Medical imaging, astronomy, nuclear power |
| Gamma Rays | Less than 0.01nm | Greater than 30 PHz (30 billion GHz) | Nuclear radiation, astronomy, cancer treatment |
Characteristics of Electromagnetic Waves
Electromagnetic waves have some unique characteristics that make them useful in various applications. These are:
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- Electromagnetic waves can travel through empty space and through different types of matter.
- Electromagnetic waves have the ability to be reflected, refracted, and diffracted, allowing them to travel around obstacles and bend around corners.
- Electromagnetic waves have the ability to be focused and amplified.
- Electromagnetic waves can penetrate through many materials, allowing them to penetrate through walls and make things such as cell phones and Wi-Fi networks possible.
- Electromagnetic waves are not affected by gravity, allowing them to be used in satellite communications.
Conclusion
Electromagnetic waves are a form of energy that can travel through empty space and through many types of matter. They have the ability to be reflected, refracted, diffracted, focused, and amplified.
They can also penetrate through many materials, allowing them to transmit energy over long distances.
These properties make them very useful in many applications including radio and television broadcasts, cell phone networks, and Wi-Fi networks.
