Ultraviolet Light: Origin, Types, Visibility & Effects

Ans. No, Ultraviolet light doesn’t generate heat. The light source with time may get warm or even hot, but UV light doesn’t transmit heat on its own. But, lower frequencies of Infrared (IR) transmit heat.

Ultraviolet light is also used in various food industries as it is completely safe, requires low maintenance, and doesn’t require the use of any chemicals or pesticides. UV lamps can effectively eliminate various microbes and kill viruses like E.Coli and Salmonella.

Ans. The wavelength of ultraviolet rays can range from 10 nm to 400 nm.

Some uses of UV rays are

1. UV rays are used in burglar alarms and security systems.
2. These rays are responsible to destroy germs and bacteria and are hence used for sterilizing surgical instruments and the purification of water.
3. It is also used to differentiate between real and fake gems.
4. It is used in the treatment of psoriasis, also in recent years, these are used for the treatment of dermatological conditions.
5. UV rays are used in the treatment of skin disorders.
6. They kill the cells of the human body by damaging the DNA. When a UV light falls on the human body, it starts a reaction between two molecules of thymine, which is further responsible for making DNA.

Ans. Ozone is very harmful at the ground level but higher up in the atmosphere, this layer plays a major role in the protection of all the living beings on the Earth. The sun spreads ultraviolet radiation which harms living beings. The ozone layer absorbs the radiation and stops them from entering the outer surface of the earth. This layer is present in the stratospheric layer of the Earth’s atmosphere. The layer which occupies a lower part of the atmosphere removes the unwanted pollutants from the earth’s surface.

Ans. Light is considered as a wave and particle both. When light is categorized as a collection of particles, it can be referred to as photons. Photons are particles that do not have a mass and can carry a certain quantity of energy. 

It has a dual nature of behaving as a particle and a wave. Therefore, the fundamental theory of light has progressed from electromagnetics to quantum mechanics.

Ans. There are chemical UV blockers, like oxybenzone and avobenzone. Apart from these, there are inorganic materials that can absorb UV rays like zinc oxide, carbon black, and titanium dioxide. Some materials are used in daily life like UV-resistant sunglasses, sunscreen for the skin, and white fabric which is best for reflecting light.

Ans. Microorganisms are simple organic structures that absorb the UV-C wavelength and cause photo-disassociation. A microbe's DNA is adversely affected first due to its weaker molecular bonds. The successive loss of genetic instructions causes the death of cells or the inability to replicate, rendering them harmless. Continuous exposure to UV-C causes uninterrupted degradation like the sun does, only significantly faster.

Ans. No, UV-C lamps don't produce ozone. But, UV-C provides exceptional conditioning of air much as the sun does outdoors. UV-C fixtures are an air conditioning component in addition to other system parts. These include coil, filters, fans, dampers, heating cores, etc. All are designed to provide a specific function in the job of processing air for occupied spaces.

Ans. The lenses of sunglasses are made up of glass, plastic, or polycarbonate with a special type of UV-absorbing coating. A good pair of sunglasses is responsible for blocking 99% of UV radiation from reaching the human eye. Tints and mirror coatings relieve you from squinting, by absorbing or reflecting intense, dazzling light in the visible part of the spectrum. The high-grade sunglasses incorporate a polarising film to combat glare from reflecting horizontal surfaces like water, sand, and snow.

Ans. Biological aerosols are also known as bioaerosols and are considered a subcategory of particles that are released from terrestrial and marine ecosystems into the atmosphere. They consist of both living and nonliving components like fungi, pollen, bacteria, and viruses. They are introduced into the air via turbulence over a surface. Over ocean surfaces, they are generated via sea spray and bubbles. They can transmit microbial pathogens and allergens to which humans are sensitive.

Ans. Radiation refers to the energy which travels through space to reach the Earth. The richest source of radiation is the sun. They are found in the form of subatomic particles with higher energy and they travel in the form of electromagnetic waves.

Types of Radiation are

1. Ionizing Radiation:
   1. It contains alpha, beta, and gamma particles.
   2. These radiations carry a charge which is more than 10eV, which is sufficient to remove electrons that are tightly bound from the outer orbit of an atom, therefore resulting in the ionizing or charging of atoms and molecules and thus breaking the chemical bonds.
2. Non-ionizing Reaction:
   1. These reactions consist of microwave radiation, UV rays, thermal radiation, infrared radiation, black body radiation, etc. 
   2. It usually produces heat that can cause severe burns.
   3. These radiations do not cause ionization or charging of atoms.

Ans. The depletion of the ozone layer is a very severe problem and several programs have been started by governments throughout the world to combat it. 

We can limit the use of vehicles on the road to reduce ozone depletion. Automobiles release a considerable amount of greenhouse gases, which can contribute to global warming and ozone depletion. 

We can avoid the use of pesticides, these can be a great source for farmers to get rid of weeds and pests but they equally harm the ozone layer. To get rid of pests, eco-friendly insecticides will be used, or the weeds can be physically removed.

Most cleaning products include chlorine and bromine, which emit chemicals into the environment and harm the ozone layer. To protect the environment, they should be replaced with natural goods.

Ans. Ultraviolet water treatment is a physical method that is not responsible for affecting the chemistry of water. It does not add color, odor, or taste to water, also it doesn’t leave harmful by-products of the treatment. This process is used by several industries as it is trustworthy, widely recognized, and well-proven technology. The UV chlorine removal process is environmentally friendly but conventional methods have drawbacks such as the disposal of spent carbon, and biofouling.

Ans. The ultraviolet rays present in the sun are a vital factor for both getting vitamin D and skin cancer. With proper use of sunscreens and other sun protection substances, people can get enough Vitamin D. There are only a few sources of Vitamin D that are present in food. These include liver oil, eggs, tuna, salmon, etc. Its deficiency causes various kinds of health concerns like osteoporosis, depression, muscle weakness, and cancer which can further cause death.

Ans. The type of energy that is released by elementary particles of the atomic nucleus by the process of release of nuclear energy is known as nuclear radiation. Depending on the usage, it can be harmful or useful for people.

Three types of nuclear radiation are emitted from the radioactive atoms:

• Alpha radiation
• Beta radiation
• Gamma radiation

Ans. Infrared waves are responsible for vibrating not only electrons but entire atoms or molecules of a substance due to their frequencies lower than that of visible light. This vibration increases the internal energy, therefore, infrared waves are known as heat waves.