Theories behind light and its rainbow colours
Let’s try and understand the rainbow magic.
During the 1600s, experiments conducted by the English scientist Sir
Isaac Newton and the Dutch physicist Christiaan Huygens, led to
two different points of view about the nature of light. These view-points
are popularly understood as the Corpuscular Theory or Particle-Theory and
the Wave Theory. According to Newton’s theory light consists of many particles that travel in a
straight line through space. This theory explains how shadows are cast and
why mirrors reflect light. It also explains how light shines through a
vacuum. Newton also discovered that white light is made up of many
colours. By using a prism, he was able to separate each colour in the form
of a spectrum from a white beam of light.
On the other hand, Huygens’ theory suggests that light travels as wave,
like ripples in a pond. This theory explains, why white light is split
into a spectrum of colours as it is refracted through a prism. It
points out that each colour of light has a different wavelength. As light
passes through different mediums such as glass or water the amount of
bending that is refraction depends on the wavelength
The shorter the wavelength the more it is bent.Red
light has the longest wavelength in the spectrum and therefore it refracts
the least. Thus, it is found at the top of the visible spectrum. Violet
light has the shortest wavelength and therefore it refracts the most. It
is seen at the bottom of the spectrum.
Nature of Light