പ്രകാശത്തിൻറെ പ്രത്യേകതകളായ റിഫ്ളക്ഷൻ, റിഫ്രാക്ഷൻ, ടോട്ടൽ ഇൻറെർണൽ റിഫ്ളക്ഷൻ, ഡിസ്പേഴ്സൺ, ഇന്റർഫെറൻസ്, ഡിഫ്രാക്ഷൻ, സ്കാറ്ററിങ്, പോളറൈസേഷൻ, ഡോപ്ലർ എഫക്ട് എന്നീ സുപ്രധാന ഭാഗങ്ങളാണ് ഇന്നത്തെ പാഠത്തിൽ ഉൾക്കൊള്ളിച്ചിരിക്കുന്നത്.
- Color having minimum wavelength
Violet
- Color having maximum wavelength
Red
- Color having minimum frequency
Red
- Color having maximum frequency
Violet
- Light that scatters most
Violet
- Light that scatters least
Red
- Color which reflects all other colors
White
- Color which absorbs all other colors
Black
- Color which absorbs maximum heat
Black
- Color which absorbs minimum heat
White
- Color which appears on the upper portion of the rainbow
Red
- Color which appears in the centre of the rainbow
Green
- Color which appears on the lower portion of the rainbow
Violet
- Distance travelled by light in one year
Lightyear
- Unit used to measure distance between stars
Light year
- One light year is
9.46×1012
- One Parsec is
3.26 light years
- Quantum theory was put forward by
Max Plank
- According to Quantum theory, energy packets in light rays called
Quantum
- Quantum of light is known as
Photon
- Phenomenon of emission of light from substances after absorption of Photons called as
Photo Luminescence
- Phenomenon of bouncing back of light when a beam of light falls on a surface
Reflection
- Bending of light when a ray of light travels from one medium to another
Refraction
- Phenomena of Mirage in deserts, Twinkling of stars, bending scale immersed in water\glass etc are due to
Refraction
- Reason for refraction of light when travels from one medium to another
Phase velocity of wave is changed but its frequency remains constant
- Snell’s law is related to
Refraction
- Fata Morgana is a term associated with
Mirage (Superior form of Mirage)
- Measure of optical density of a medium is
Refractive index [Speed of light in vacuum/Speed of light in medium]
- Refractive index of Vacuum
1 [Ice : 1.31, Water : 1.33]
- Refractive index of Diamond
2.42
- Working principle of Optical fibre, endoscopy, Vehicle reflectors, Binoculars
Total Internal Reflection
- Sparkling of Diamond is due to
Total internal reflection in high refractive index
- Splitting of composite beam of light into its constituent colors is called
Dispersion of light
- Dispersion of light is discovered by
Issac Newton
- Device used to split composite light into constituent colors
Prism
- Rainbow is caused by
Total internal reflection, refraction and dispersion of light by water particles
- Red color in rainbow is seen at an angle of
42.8 Degree
- Violet color in rainbow is seen at an angle of
40.8 Degree
- Shape of rainbow while seeing from space
Circle
- Distribution of light when two or more high waves superimpose each other is called
Interference
- Colors in soap bubbles, oil layers etc are due to
Interference
- Interference was first observed by
Thomas Young
- Working principle of Holography\Hologram
Interference
- Process of spreading out of light into geometrical shadow of obstacle is called as
Diffraction
- Projector in film theatres works on the principle of
Diffraction
- Rings around the sun, Fringe pattern of CD etc are due to
Diffraction
- Blue color of Sky, Reddening of Sun at sunrise and sunset are due to
Scattering of light
- The light color which scatters most
Violet (Having shorter wavelength)
- The light color which scatters least
Red (Having longer wavelength)
- Black color of sky in Moon is due to
Absence of scattering of light as there is no atmosphere
- Phenomenon of confining the vibration of a transverse wave to a particular direction is called
Polarization
- Brewster’s Law is associated with
Polarization of Light
- Example of natural polarizing material
Tourmaline
- Polaroids are using in
Aeroplane and car windows, sunglasses, Three-dimensional pictures
- Light scattering by the particles in a colloid is known as
Tyndal effect
- Example of Tyndal effect
Sunlight passing through mist, blue color seen in smoke emitted from motorcycles
- Change in frequency of a light or sound wave when source or observer moves with respect to the other is known as
Doppler effect
- Increase in frequency (decrease in wavelength) of visible light when it moves towards observer is called
Blue Shift
- Decrease in frequency (Increase in wavelength) of visible light when it moves towards observer is called
Red Shift
- Blueshift, Red Shift, High pitch of siren approaching ambulance is due to
Doppler effect
(To be Continued…)