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Ultraviolet Waves

An informative article describing UV wavelength, its origin, discovery, the sun as a primary source of UV light and the types of the wavelength of UV rays.

Ultraviolet waves are a part of the electromagnetic spectrum and lie in the region of short-wavelength radiations. It resides between X-Rays and the visible light and has a wavelength of 10 – 400 nm, which is shorter than that of visible light but longer than the wavelength of X-rays. As it has a wavelength shorter than the wavelength of the visible light, the human eye can not see these waves, but a few insects like bumblebees are able to see them. These rays have an energy upto 100 eV.

Out of the entire electromagnetic spectrum, the UV rays are the ones causing sunburns on our skin. These rays are harmful and are blocked by the ozone layer from entering to the earth’s atmosphere. Anyhow, due to increasing pollution, the UV rays have started to enter the atmosphere of earth a little.

General Features of Ultraviolet Rays:

  1. Wavelength: 10-400 nm
  2. Frequency:  8 × 1014 – 3 × 1016 Hz
  3. Forms 10% of the EM rays produced by the sun
  4. Colours: Purple or Violet
  5. Energy: Upto 100 eV

Subdivision of Ultraviolet Region

The ultraviolet region of the EM spectrum has a division into three sub-parts, namely, the near ultraviolet, the far ultraviolet, and the extreme ultraviolet. These divisions have been made on the basis of energy and hence the wavelength of the radiations.

The Near Ultraviolet

This part of the UV region is abbreviated as NUV (Near Ultraviolet). The NUV lies nearest to the visible region.

The Extreme Ultraviolet

This part of the UV region has been abbreviated as EUV (Extreme Ultraviolet). The EUV lies nearest to the X-Rays and hence is the most energetic out of the three divisions.

The Far Ultraviolet

This part of the UV region is abbreviated as FUV ( Far Ultraviolet). It falls between the EUV and the NUV and hasn’t been much talked about or researched about.

Types of Ultraviolet Radiations

The Ultraviolet Rays have been classified into three categories: Ultraviolet A (UVA) [400-315 nm], Ultraviolet B (UVB) [315-280 nm] and Ultraviolet C (UVC) [280-100 nm].

This classification has been made on the basis of their varying wavelengths. Overexposure to the UBV can also cause damage to the DNA and other cellular organs. The atmosphere completely soaks the UVC and causes the most amount of harm among the three types.

Examples of Ultraviolet Waves:

The examples of processes or objects where ultraviolet waves are used are:

  1. A disinfectant machine uses Ultraviolet Waves for the process.
  2. A Lamp using Ultraviolet Waves
  3. Room sterilisation done with the help of Ultraviolet Waves.
  4. Some Skin diseases are also cured by Ultraviolet rays.
  5. Ultraviolet rays are used for detanning
  6. Northern lights are created by the Ultraviolet Waves.
  7. Decorations purposes are also sorted by using Ultraviolet Lights at many places.

Benefits of Ultraviolet Waves

  1. It is used in various different types of fluorescence, phosphorus, and incandescent lights.
  2. It helps in producing Vitamin D.
  3. It is used in industrial, medical and dental processes.
  4. It is used to cure resins and inks and phototherapy.
  5. It is used for sterilisation, killing microbes and in operating rooms.

Harms of Ultraviolet Waves

  1. When overexposed to it, it causes sunburns, premature ageing, skin cancer, and immune system damage.
  2. Some medical drugs like antibiotics, birth control pills, and other cosmetics can increase eye or skin sensitivity to UV rays.
  3. Ultraviolet rays might cause blindness or cataract in the eye if exposed to it without any glasses.

Conclusion:

In this article about ultraviolet rays, we have discussed its features in the electromagnetic spectrum like that of wavelength (10-400 nm), frequency, energy, etc.

We have talked about the subdivision of the ultraviolet region into far, extreme, and near ultraviolet.

We have also mentioned the types of ultraviolet radiations that are UVA, UVC, and UVB; out of which, UVC has the most amount of energy and is the most harmful out of all.

We have talked about some of the examples where UV rays are used. The benefits of UV rays are to provide Vitamin D, radiant lighting, sterilisation, etc. The harmful effects of UV rays are that it causes sunburns, skin problems, skin cancer, immune system damage, loss of eyesight, cataract, and premature ageing if overexposed to it (or in the case of not using a UV protection).

faq

Frequently asked questions

Get answers to the most common queries related to the CBSE class 12 Examination Preparation.

What is UV radiation?

Ans:Ultraviolet radiation is that portion of the electromagnetic spectrum that extends from the violet or short-wave...Read full

Who discovered UV rays?

Ans:The German physicist Johann Wilhelm Ritter discovered UV rays in 1801.

What are the varieties of UV radiation?

Ans:Sunlight is the most common form of UV radiation. It produces three main types of ultraviolet rays, namely UVA r...Read full

Which are the most harmful rays out of all the types of UV radiation?

Ans:The most harmful rays are UV-C rays, entirely absorbed by the atmosphere.

What is the name of the scientific scale on which UV rays are measured?

Ans:The scientific scale on which the UV rays are measured is the Electromagnetic Spectrum.