That white light is made up of all the colours of light mixed together.
dispersion of white light into its constituent colours
Isaac Newton's triangular prism was likely made of glass, a common material for prisms during his time due to its transparency and ability to refract light.
triangular prism
prism
Newton prove gravity by means of an apple falling on his head
Isac newton
Sir Isaac Newton discovered that white light was made of seven different colors in the 17th century. He was able to prove that when some of the white light from the sun passes through a prism shaped piece of glass, the light scatters into a spectrum, which is a spectrum of what we know as the rainbow.
Newton explained his theory
When the colors formed by a prism is made to pass through a second prism, it results in producing white light. Newton's experiment demonstrated in this method is recombination of light. Conversely dispersion can be demonstrated with the help of a single prism.
he used a prism?
Newton
a prism, and the telescope