understanding formation of a rainbow by tin wei heng
DESCRIPTION
Rationale Understand the formation of rainbow Understand how light disperses better Better understand the reflection and refraction of lightTRANSCRIPT
Understanding Formation of a Rainbow
By Tin Wei Heng
Contents Rationale Colours of a rainbow Introduction to light dispersion Refraction and reflection of light in water
droplet Maximum angle at which light should leave
droplet to see rainbow Rainbow as a 3D cone
Rationale Understand the formation of rainbow Understand how light disperses better Better understand the reflection and
refraction of light
Colours of Rainbow Red Orange Yellow Green Blue Indigo Violet The colours of the Rainbow are also known
as the colours of light when it is dispersed
Dispersion of light Dispersion of light occurs when light
passes through from one medium to another
This causes different colours to refract at different angles
This phenomenon splits white light into the colours of a rainbow
Refraction and reflection of light in a water droplet Light is first refracted entering the
surface of the raindrop,reflected off the back of the drop, and again refracted as it leaves the drop
Angle The most intense light can only leave the droplet
at an angle of 42 degrees to see the rainbow This is because if the sun is higher than 42
degrees, the rainbow will then be below the horizon and usually cannot be seen
This is because there are not usually sufficient raindrops between the horizon(eye level) and the ground
Exceptions occur when the observer is high above the ground E.g. Ferris wheel, aeroplane
Formation of a Rainbow(Complete) Light first enters the droplet at an angle
of 42 degrees or less It is then refracted when entering the
surface of the droplet The light is then dispersed into different
colours(colours of the rainbow) Light is then reflected off the back of the
raindrop and again refracted as it leaves the drop
After all this hard work you get…….. TADA!!!!!!
Thank You