When did isaac newton discover spectrum, rectilinear propagation of light,& equation of velocity of sound?
In 1665 Newton made his first observations concerning the spectrum and the propagation of light. In 1672 he reported on his observations to the Royal Society. In 1704 he published his investigations in “Optics”. He invented the first form of calculus, solved many mathematical problems, and came up with what is now known as Newton’s Law of Cooling – that the rate at which a body loses heat depends on the temperature difference between the body and its surroundings. In mechanics, as well as the three laws and the Law of Gravitation, he also discarded the misleading centrifugal force and replaced it with the more useful “centripetal” force. He invented the reflecting telescope ! And did the first studies on the interference of light. There is no record of him being involved with the velocity of sound. It was probably too easy for him. Having already been well studied.
