Introduction and principle of UV
INTRODUCTION TO UV RADIATION:
Electromagnetic radiation is always emmited by the sun of various wavelengths.Many radiations are visible to our eyesight but many are not.the ray beyond the violet light which is invisible to our eyes is the uv rays.
UV RADIATION IN BRIEF
Basically the electromagnetic spectrum are various kinds . This spectrum includes radiations from radio waves to the visible light, and it ranks the various waves on the basis the degree of energy they emit and their wavelength. UV rays fall at the high energy/short wavelength end of the spectrum .It is one of the most dangerous form of spectrum.
The sun is a major source of emmision of uv rays and it is invisible to human eyes . The ability of the wavelenght to harm the humans is its shortness . Ultraviolet (UV) radiation that reaches the Earth’s surface is in wavelengths between 290 and 400 nm.Which is shorter than wavelengths of visible light, which are 400 to 700 nm.
Basically UV radiation are of twoo types that penetrate our atmosphere — UVA and UVB radiation,where UVA radiation is a longer wave than UVB radiation.
UV-A Radiation at the longer UV wavelengths are of 320-400 nm, which plays a helpful and important role for the formation of Vitamin D within the skin,and causes harmfull effects which causes sunburn in the human skin and cataracts in animal eyes. Whereas the incoming radiation at the shorter wavelengths the 290-320 nm comes under the UV-B .
DNA can readily intake UV-B radiation, which mainly changes the shape of the molecule .Many distortion occurs which ruptures the cell and a human may die.
It was once interpreted that UVA rays were “safe” compared to UVB rays by the researchers . This was an assumption made as we know UVB radiation is reason for the most obvious damage to the surface of the skin which includes many forms of skin cancer. UV radiation causes skin cancer wrincles,premature aging and death
UV RADIATIONS MEASURMENT:
A wellknown UV sensor is used by the Hong Kong which is used to measure the intensity of the UV radiation at the King’s Park Meteorological Station. Any type of uv radiation can be measured here This type of sensor has a response which approximates the response of skin to UV radiation of different wavelengths.
PRINCIPLE OF UV RADIATION:
the principle involves the intake of electromagnetic radiation by the substance in the UV visible regions of the spectrum. This will result in changes in the electronic
QUESTION AND ANSWER:
Q1. What is the range of UV radiation?
Ans: The range of UV radiation wavelengths lies between 320-400 nm.
Q2. How many type of UV radiation are there?
Ans: UVB and UVA
Q3. Which type of UV radiation is more harmful?
Ans: UVB radiation is more dangerous because it causes skin cancer .
Q4. What is the principle of UV radiation?
Ans: absorbtion of electromagnetic radiation.
Q5. How the UV radiations are harmful to human body?
Ans: causes skin cancer,wrinkles,affects the DNA,ruptures the blood cells.