Light

In Glogpedia

by woodster1
Last updated 5 years ago

Discipline:
Partners
Subject:
Energy

Toggle fullscreen Print glog
Light

the physics of

LIGHT

Light also known as electromagnetic spectum is the range of which the wave lenghths or frequency radiation spreads to. Light is the cause we an see object in various colours

Scientific Terminology:

Reflection: is the act of a light ray rebounding off a solid obect, the opposite of being absorbed.Apsorbtion: is the movement of a wave being taken into an object.Frequency: are electromagnetic waves which vibrates at a rate of per second. Short static wavelengths are the higher frequencies and the slow long wavelengths are the lower frequenciesCornea: is the transparent outer layer on the front, it gives it the ability to adjust eye so it can focus the light to the retina.Crystalline lens: is the internal part of the eye where it lets you concentrate on the incoming light rays.

Amplitude: is the terminology they use to measure the rate of the wave lengthsLight Energy: also known as 'electromagnetic spectrum' is the range of which the wavelengths or frequency radiatio spreads to. Energy can never be lost it only changes form.Concave Mirrors: is curved inwards, when a light hits the inner layer of the mirrior it reflects to a focal point.Convex Mirriors: is curved outwards, when a light lay hits the mirror it reflects in the angle off the focal pointNm: Stands for nano meter, 1,000,000 nano meters is equivalent to 1mm.

When white light hits specific objects such as rain drops or transparent prisms the light refracts slightly differently when it enters the object then reflects off the inner layer and then escaping out transforming into a colourful rainbow. Secondary rainbow are when the light reflects twice within the object causing it to escape out in the opposite colour order, where red is at the bottom and violet at the top.

Light is an energy, their needs to be a light source to form and release the energy. Their is two main sources of light, Incandescent and Luminescent. Incandescent sources produce heat or combustion to generate the light source, the filament in a light bulb will create the visible spectrum causing it to glow white, for example the sun, stars, molten metal and a light bulb are all incandescent. Luminescent sources are generally cooler, a cause could be chemical reacations, for example glow sticks, computer screens, Fluorescent lights and Glow worms are all luminescent.

Retina: a part at the back of your eye where it contains light sensitive cells, once hit with light it triggers a message to your brain causing a coloured visual image. The Retina contains two photorecepters rods and cones. Cones only enable us to see things in colour and Rods only enable us to see the shades such as black, grey and white.Shadows: is the when an object is blocking the light to the surface causing us to see the shadow, Refraction: is the bending of light, when light travels through through a transparent substance into another. This is the cause we have lenses, magnifiing glasses, prisms and rainbowsPolychromatic Light: is white light it is made up of all the colour in the rainbow.Monochromatic Light: is light that is a specific colour such as lasers.

Light travels at 299,792,458 meters per seconds. That is nearly 300, 000 kilometers per second, If the circumference around the earth is 40,000 kilometers so in 1 second light could travel around earth 7 and half times. Light travels in straight lines, it will keep moving forward until it hits an object. The evidence is shadows of light travelling in a straight line. When light hits an object, it blocks the light reaching some of the suface causing us to see the shadow. Shadows aren't totally dark because some light has reflected off other objects surrounding it causing it to be not totally dark.

We see objects in various colours because of light. When light rays hits an object it absorbs or reflects the wavelengths, the colour that we see is the ones which are reflected back. Visable light waves consist on various wavelengths, different wavelengths are different colours. These wavelength range from 700 nm as red on one end and 400 nm as violet on the other end of the spectrum. When light rays come towards the eye the crystalline lens and the cornea adjust your eyes to concentrate on the incoming light rays. Once the light ray hits your retina you will be enabled to see the coloured object in front of you. If the light is not bright enough it causes it to look very dim, like at night.

The Primary colours of light are green, red and blue. When mixing these colours in different proportions it will create the visible light spectrum. Polychromatic Light is white light which is made up of all the colours of the rainbow and Monochromatic Light only shines one specific colour. Different frequencies equal different colours as the diagram below.

The Refraction of light in a transparent prism becomepopular after the release of Pink Floyd Dark Side of the Moon, 1973

The reflection of light is when a light ray hits an object and rebounds off. Their are two types of relection, specular and diffuse. When the surface is smooth and shiny like water and glass, the light will reflect off the surface in the same angle as it came in. This called specular reflection. The light ray that is incoming towords the object is named the angle of incidence and the light ray that is reflecting of the object is named the angle of reflection. When the surface is rough, the light will reflect in different directions. This is called diffuse reflection.

Their is not only flat mirrors their are concave mirrors and convex mirrors too. A concave mirrors is the inner part of a semi circle so if a light ray hits anywhere on the inner side of the semi circle it would reflect to a focal point as the diagram below. A convex mirror is the opposite side of the concave the outer side of the semi circle so if a light ray hit anywhere on the outer side of the semi circle it would reflect off in the angle off the focal point as the diagram below


Comments