Question
Briefly explain about light.
✓
Answer
$\rightarrow$ The human eye is only sensitive to small range of electromagnetic spectrum.
$\rightarrow$ This region is known as visible light.
$\rightarrow$ The wavelength of this region is $400 \ nm$ to $750 \ nm.$
$\rightarrow$ Two important points about light:
$(i)$ Light travels with enormous speed. Speed of light is limited and measurable.
$\rightarrow$ Its presently accepted value in Vacuum is $c = 2.99792458 \times 10^8 m/s$
$\rightarrow$ For ease of calculations the velocity of light in free space is taken as $c = 3 \times 10^8 m/s$
$(ii)$ Light travels in a straight line.
$\rightarrow$ This region is known as visible light.
$\rightarrow$ The wavelength of this region is $400 \ nm$ to $750 \ nm.$
$\rightarrow$ Two important points about light:
$(i)$ Light travels with enormous speed. Speed of light is limited and measurable.
$\rightarrow$ Its presently accepted value in Vacuum is $c = 2.99792458 \times 10^8 m/s$
$\rightarrow$ For ease of calculations the velocity of light in free space is taken as $c = 3 \times 10^8 m/s$
$(ii)$ Light travels in a straight line.
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