Question

Give a brief account of the models regarding
the nature of light before the 20th century.​

Answer 1

$\huge\underline{\underline\mathtt{Answer:-}}$

Newton, and the Greek philosophers preceding him, thought that light was made up of tiny material particles which are emitted by a source and travel in straight lines at infinite speed. The 'bouncing off of these particles from surfaces into our eyes made the objects visible. But then it was discovered that light behaves like waves - experiments on interference anddiffraction in the 17th century could only be explained if we assume a wave model of light. French physicist Fresnel showed that wave theory can also satisfactorily account for rectilinear propagation of light, thus dispelling Newton's main objection to the wave theory.The fact that the speed of light was finite wasfirst determined in 1675 by Danish astronomer Römer and later in 1849 by French physicistsFizeau and Foucault. In the mid-19th century,British physicist Maxwell concluded from his electromagnetic theory that light was an electromagnetic wave which travel in free space with a speed c = 2.99792458 x $\ 10^{8} m/s.$