Please enable JavaScript.
Coggle requires JavaScript to display documents.
Light and Colorful World - Coggle Diagram
Light and Colorful World
Refraction of Light through Prism
Different colours travel through a glass prism at different speeds.
The angle between the extended incident ray and the emergent ray is called the angle of elevation.
Scattering of Light
Blue colour of the sky
Reddishness of the sun at sunrise and sunset
Refraction of Light : Laws
Snell’s Law : The ratio of the sin of angle of incidence to the angle of reflection is always constant (n = sin i/sin r)
The incident ray, the normal and the refracted ray all lie in the same plane
Formula for focal length
Mirror Formula : 1/f = 1/v + 1/u
Lens Formula : 1/f = 1/v - 1/u
Reflection of Light : Laws
The incident ray, the normal and the refracted ray, all lie in the same plane
The angle of incidence is equal to the angle of reflection : angle i = angle r
Mirrors
Convex mirror : produces virtual images
Uses
Found indoors and outdoors on vehicles
Security cameras
Plane mirror : produces virtual images of same size at same distance
Concave mirror : can produce virtual as well as real images
Uses
Flood lights
Reflector for projector lamps
Torches and headlights
Solar devices
Position of object
At C : Image at C (Real)
At infinity : Image at focus (Real)
Between F and C : Image beyond C (Real)
At F : Image at infinity (Real)
Between pole and F : Image behind the mirror (Real)
Between infinity and C : Image between F and C (Real)
Lenses
Concave lens - diverging
Uses
Eye glasses and contact lenses
Flashlights
Peepholes
Compound microscope
Uses
Compound microscope
Telescope
Simple microscope
Camera spectro meter
Spectacles
Position of object
At infinity : Image at F2 (Real)
Beyond 2F1 : Image between F2 and 2F2 (Real)
At 2F1 : Image at 2F2 (Real)
Between F1 and F2 : Image beyond 2F2 (Real)
At F1 : Image at infinity (Real)
Between F1 and optical center : Image on the same side of the lens as the object (Virtual)
Magnification
Mirrors : m = -v/u = h’/h
Lenses : m = v/u = h’/h
Refractive Index
n = Velocity of light in medium 1/Velocity of light in medium 2
It has no unit
Power of Lens
Power is measured in Dioptres (D)
P = 1/f (in meters)
Dispersion of Light
Shows Tyndall Effect
Splitting of light into its component colours
Red colour deviates the least and violet deviates the most
Atmospheric Refraction
Reflection of light by the earth’s atmosphere
Planets do not twinkle
Advanced sunrise and delayed sunset
Twinkling of stars
Formation of Rainbow
The phenomenons associated are dispersion, refraction and total internal reflection
