Light has been an interesting study throughout the ages of experiments and studies. It was the Ancient Greek period when Pythagoras thought that we shoot out beams from our eyes that make us see objects. On the other side, Epicurus believed that the objects illuminate so that our eyes could see them. Later an Arabian scientist Ibn Al-Haytham used the studies of the previous theories to prove that light gets reflected by objects and enters our eyes, making us see the object. For this theory, he also presented an experiment that consisted of lenses and mirrors, or geometrical optics. Today we know a lot about light and have plenty of applications running all around us, but how much do we know? Here are things about light that you should know.
Light is a wave
Reflection and refraction are the two phenomenons that prove the behavior of light as a particle. Reflection is when the light falls on a reflective surface like a mirror and makes a reflected beam that makes the same angle as the incoming beam if it is a flat surface. Refraction is when the light travels from one transparent medium to another, such as through air and water. When this happens, the light deflects from its path when it enters another medium. This was the theory of Issac Newton to conclude that light behaves as a particle. However, a recent theory in the 19th century by English physicist Thomas Young proved that life behaves as a wave. In his double-slit experiment, he aimed a beam of light on a piece of cardboard with two slits. A wave has four properties – amplitude, wavelength, frequency, and wave speed. Light can act as a wave and expand in all directions. It can interfere with other waves and even bend around corners. It can also carry energy and momentum while also interacting with matter.
Light is an electromagnetic wave
Light can travel without the need for any medium. Light is an electromagnetic wave that is its own medium. The electric field waves and the magnetic field waves propagate each other and do not require any other medium to exist.
Light can interact differently with matter
The electromagnetic spectrum is wide and consists of different levels of wavelength. It consists of infrared, radio, microwaves, visible light, X-rays, gamma rays, etc. All electromagnetic waves travel at the speed of light but interact differently with the matter. While X-rays can pass through your skin, visible light cannot act in such a manner.
Light enters our eyes
We cannot see and object if the light does not pass through our eyes. Light can enter in two ways, either as a source such as a light bulb or a light reflected off an object. Without the presence of light, the eyes will only be able to see the color black.
Everything produces light
Every object emits some kind of electromagnetic radiation but in the infrared spectrum, which prevents human eyes from seeing it. You can use an infrared camera to spot objects in the dark. The objects create shorter wavelengths as they grow hotter. You can detect the objects in different colors based on their temperature.