Facts to Remember | |
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The speed of light in vacuum is 186,000 miles per second or 300,000,000 m/s | |
The speed of light is slower in transparent mediums like water, glass and air and depends upon the refractive index of the medium. | |
Light is the visible part of electromagnetic spectrum and the frequency of light lies between 4 x 1014 Hz to 8 x 1014 Hz | |
Colour of light with smallest wavelength is Violet with a wavelength of about 400 nanometers | |
Colour of light with longest wavelength is Red with a wavelength of about 650 nanometers | |
The study of properties and behaviour of light is known as Optics | |
Sunlight takes 8 minutes and 20 seconds to reach the Earth. | |
Light takes about 1.3 seconds to travel from the Earth to the Moon. | |
Three dimensional imaging using interference of light is known as Holography | |
System of light excitation used in surgeries, printers etc. is LASER | |
The colour of light which is most conducive to photosynthesis is Blue |
Phenomenon | Visible Effect |
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Refraction of light |
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Dispersion of light | Rainbows are formed |
Interference of light | Beautiful colours are seen in soap bubbles and oil films on water |
Scattering of light rays of small wavelengths | Sky appears blue Sun appears red during sunrise and sunset |
1. The speed of light in vacuum is m/s
2. The colour of light with the smallest wavelength is
3. The study of properties and behaviour of light is known as
4. Rainbows are caused due to of light.
5. Sunlight takes minutes seconds to reach the Earth.
6. The colour of light with the longest wavelength is
7. The colour of light which is most conducive to photosynthesis is .