explain the experiment conducted by Newton to show that white light contains seven colours. sun appears red in colour during sunrise but appears white at noon. explain with the reasons
Answers
Answer: Newton’s colour spectrum Newton introduced the term ‘colour spectrum’ and although the spectrum appears continuous, with no distinct boundaries between the colours, he chose to divide it into seven: red, orange, yellow, green, blue, indigo, and violet. Newton chose the number seven because of the ancient Greek belief that seven is a mystical number.[5] Newton showed that every colour has a unique angle of refraction that can be calculated using a suitable prism. He saw that all objects appear to be the same colour as the beam of coloured light that illuminates them, and that a beam of coloured light will stay the same colour no matter how many times it is reflected or refracted. This led him to conclude that colour is a property of the light that reflects from objects, not a property of the objects themselves The sun during sunrise is the furthest from the point of view as it's just peering over the horizon. Red light refracts less then an all the other colours of light thus reach further than the other colours so your only able to see the colour that can reach you which will be red. While during the day the sun is much closer and all the colours of light can reach you thus you see the combination of those lights which turns out to be white.
Explanation:
Sir Isaac Newton (1642-1727) exerted a profound influence on many aspects of science, notably on optics and dynamics, through his great mastery of precise experiments, but he was also a celebrated writer on religion, scientific method and the philosophy of science. He was born at the Christmas following the death of Galileo and would later declare his indebtedness to that Italian and to the Pole, Copernicus:
If I have seen a little farther than others it is because I have stood on the shoulders of giants
The Prism Experiment
Painting of Newton prism experiment
His investigations into optics commenced in 1666 at the end of an annus mirabilis when, at home in Woolsthorpe, Lincolnshire due to the bubonic plague which was raging in Cambridge, he investigated gravity, calculus and the laws of motion. He determined to ‘try therewith the celebrated Phaenomena of Colour’. It had been thought previously that colour was created by the mixing of light and darkness. Newton noted, however, that the blended print on the white page of a book appears grey, not coloured, when viewed from a distance. His experiments in bending light through prisms led, eventually, to the revolutionary discovery of the existence in white light of a mixture of distinct coloured rays, distinguishable when refracted in a prism. In his first experiment he projected the light via a round hole in his shutters.