Question

Analyze the diagram of the solar spectrum and write answers.
A. Which radiation has a wavelength greater than visible light in this spectrum?
B. Which color has the highest frequency in the visible part of the solar spectrum?
C. Write one merit and demerit of infrared and ultraviolet radiations.

Answer 1

Hint: Solar spectrum is also known as electromagnetic spectrum. Ultraviolet, visible and infrared are distributions of the electromagnetic spectrum. According to frequency range Ultraviolet, visible and infrared are in descending order. Ultraviolet rays travel faster than visible and infrared rays the visible and then infrared rays. Hence the frequency of ultraviolet must be greater. We know that frequency is a reciprocal of wavelength. Visible light has seven spectra. Violet has the lowest wavelength than red.

Complete step-by-step answer:

To answer all these questions first we need to understand the three terms: Ultraviolet Rays, visible light and infrared Rays first we will see what ultraviolet Rays is and what are its properties. Similarly we will see for visible light an infrared Rays.
Ultraviolet rays: Ultraviolet Rays were discovered by scientist Ritter. Ultraviolet Rays are the part of electromagnetic waves of very short wavelengths ranging from${{10}^{-8}}\text{ to 4}\times \text{1}{{\text{0}}^{-7}}$. Their wavelengths are shorter than those of visible light and particularly shorter than the violet light which is a spectrum of visible light. They can be obtained by passing discharge through hydrogen and xenon. Ultraviolet Rays also cause photoelectric effect. When they are incident on metal surfaces, electrons are emitted by these surfaces.
Since wavelength of ultraviolet Rays ranges from ${{10}^{-8}}\text{ to 4}\times \text{1}{{\text{0}}^{-7}}$ which is a smaller than wavelength of visible light and infrared light. And we know that frequency is reciprocal of wavelength, therefore frequency of ultraviolet rays is greater than visible and infrared rays. Frequency of ultraviolet rays ranges from ${{10}^{15}}to{{10}^{17}}Hz$
Visible light: Visible light is the most important and family form of electromagnetic waves. It is a part of the electromagnetic spectrum. It can be detected by the human eye, that is we can see the spectrum of visible light. Example is rainbow. These waves are having wavelengths ranging from $4\times {{10}^{-7}}\text{ to 8}\times \text{1}{{\text{0}}^{-7}}m.$ therefore this wavelength range is called of visible light. The visible light is emitted due to atomic excitation. Visible light forms in a narrow part of the electromagnetic spectrum. These lights consist of different colors ranging from red to violet. Different wavelengths give rise to different colors. The wavelengths of red color are larger while those of the violet color are small. Therefore the frequency of violet light is more than the frequency of red light.
Since wavelength of visible light ranges from $4\times {{10}^{-7}}\text{ to 8}\times \text{1}{{\text{0}}^{-7}}m.$which is a smaller than wavelength of infrared light and greater than ultraviolet rays. And we know that frequency is reciprocal of wavelength, therefore frequency of visible light is greater than infrared rays and smaller than ultraviolet rays. Frequency visible light ranges from $4\times {{10}^{14}}\text{ to 8}\times \text{1}{{\text{0}}^{14}}Hz.$
Infrared radiations: Infrared Rays or radiation was discovered by Hershell. Infrared rays are having wavelengths ranging nearly from${{10}^{-6}}\text{ to 1}{{\text{0}}^{-4}}$. All hot bodies are sources or infrared Rays. About 60% of the solar radiation are infrared in nature. The thermocouple, thermopiles, and bolometers are used to detect infrared Rays. When infrared Rays are incident on any object, the object gets heated. They are fake photographic plates. D odds strongly absorbed by glass.

Note: The only electromagnetic waves known in Maxwell’s time were light waves later on infrared Rays which are electromagnetic waves having wavelengths greater than those of their lights were discovered. Soon after ultraviolet Rays which are electromagnetic waves having wavelength smaller than those of ultraviolet light were discovered. The orderly distribution of electromagnetic waves according to their wavelength in the form of distinct groups having different properties is called electromagnetic spectrum or solar spectrum. Electromagnetic spectrum contains different electromagnetic waves that differ from one another in frequency and wavelength. The sources that produce these waves and detectors that detect them are different for different wave spectrum of electromagnetic radiation. It has no upper or lower limits that is a sharper bond if all regions overlap there are no gaps pleasant.