All About Light-Physics

Light waves are a form of electromagnetic waves, which consist of patterns of electric and magnetic energy. The visible spectrum is only a small part of the electromagnetic spectrum-the

We benefit greatly the benefits of long distance communication, eating food from different parts of the countries without fear of spoilage, radiation treatment, and heating up food in a matter of minutes, and a myriad of other wonders all do the wonders of waves, be they sound waves as well as light waves. In this timeline, we will look at all of the different light waves, their history, and their benefits.

Light is a type of energy. Light behaves like a wave because it acts as a disturbance in the magnetic and electric field of space. Light can behave as a particle, because it sends all its energy to one place. A particle of light is called a photon. Photons can be absorbed into objects, bounce

Electromagnetic radiation behaves both as particles (called photons) and as waves. Wavelength () and frequency () are related according to the equation

Niels Bohr was another large piece of the Solvay Conference in 1927. He and Einstein were the stars of the show, as they both battled to prove their theories. Niels Bohr’s theory was about “Quantum Mechanics”. Even today we still use this theory. The teachers teach this to the students, and it is the best theory that we know about. The theory is that we use different orbitals where the electrons will travel around the atom. The different orbitals mean the different energy

Electromagnetic radiation are electromagnetic waves, or photons, that are emitted by astronomical bodies and travel in all frequencies (Auger, 1964). Particle radiation, on the other hand, are charged particles traveling at high speeds, protons, and even nuclei of other heavier elements. These particles tend to travel near the speed of light, so fast that their electrons are completely striped from

This leads to a justifiable case where light can have mass. For instance, if a photon was placed inside a box of mirrors, it will travel and continuously bounce back and forth from one end to another. This creates energy and momentum which are conserved inside the box.

Let’s look at one other wave property of light. Light travels in transverse waves and this property is demonstrated by a phenomenon called polarization. Polarization means that the waves of light are restricted in their direction of vibration. Think of a horizontal string that you shake from one end. If you shake the string up and down, you will get up and down, or vertical, waves. If you shake the string back and forth, you will get horizontal waves. In this way, the string is said to be polarized. Vibrating electrons emit waves that are also polarized. A vertically vibrating electron emits light that is vertically polarized and a horizontally vibrating electron emits light that is horizontally polarized.

The color wheel relates the wavelengths of transmitted light to absorbed light. Objects absorb different amounts of white light, which is what makes an object have its unique color. The white light is what in turn makes color. While there were many theories throughout history on light, the first theories about light were created by the Ancient Greeks. These theories tried to describe light as a ray which moved directionally to a point. Pythagoras was best known for his theorem of the right triangle that was made up of the assumption that vision was made from light rays that came out of a person's eye and hit an object. This is true in many senses. In reflection, when light hits a smooth surface, it hits then bounces off. A reflected ray always comes off the surface of a material at an angle equal to the angle at which the incoming ray hit the surface. However, when light bounces off a rough surface, light reflects at numerous angles

Everything that has a color (excluding transparent and colorless matter) transmits, absorbs, and/or reflects energy from light. Plants, light most objects, reflect and absorb light. The color of an item is the wavelength of that color being reflected while all other wavelengths

Visible light consists of several different colours. The different colours represent different wavelengths of the radiation spectrum. One lumen is equivalent to 1/680 Watt of light with a wavelength of 555 nm. The relationship between illumination and visual response renders the lumen the preferred photometric unit of luminous flux for practical applications. For example, the electric light bulb emits light which consist of many different wavelengths. The visible light waves consists of a continuous range of wavelengths or frequencies. There are numerous of situations that could happen when a light wave with a single frequency strikes an object. An object could absorb the light wave. In this case, the energy will be converted to heat. However, the object could reflect the light wave depending on the material of the object. Furthermore, the object could transmit the light waves. Therefore, the manner in which visible light interacts with an object is dependent upon the frequency of the light and the nature of the atoms of the object. Therefore, visible light affects the luminous intensity, thus it might not obey the inverse square law.

Light is a form of energy and composed of different wavelengths. When the light exposed to an object, the light could be reflected at the surface of the object (specular or diffuse), and it could be absorbed or scattered within the object, or it could refract or totally transmitted through the object44, 45. The wavelengths (colors) that are reflected, refracted or transmitted are perceived by receptor cells (i.e. rods and cones) in the eye and recognized by the brain as a specific color. The wavelengths of visible light range from approximately 400 to 700 nm45, 46. The wavelengths that are transmitted, refracted or reflected create the color that is perceived and till about the translucency level of the material. If all light is transmitted, the material will appear completely transparent. If all light is absorbed, the material will appear completely opaque, and the color black is perceived. However, if some of the wavelengths of visible light are absorbed and others reflected, refracted, or transmitted, the color that is perceived corresponds to the wavelengths that are reflected, refracted, or transmitted, and the level of translucency is depend on the amount of the light that transmitted through the material9, 44-46. Moreover, the reflection of the light depends on the surface texture of the restoration. Thus, a smooth surface increases the specular reflectance, in which the angulation of light reflection is equal to the angle of the light source. This reveals more of

Light is made up of photons that has many characteristic of both a wave and a particle. This characteristic of particles acting like a wave and a particle is called the wave/particle duality. It acts like a wave because light has certain frequency in which determines the type of light it is. This property is very similar to sound waves where the wavelength changes how the soundwave sounds to the human ear. Light can be a different electromagnetic wave like UV light, gamma ray, X ray, and etc depending on the wavelength and frequency. Light also acts like a particle because of the photoelectric effect. This was discovered by Albert Einstein’s experiment. The experiment consisted of shooting photon into a vacuum tube. The results of that experiment was that light did not increase the electron output when increasing the intensity of the light. Water is made up of two hydrogen and one oxygen. At room temperature(which is 21°C or about 70°F), water is in liquid form. Within water, the water molecules are moving around giving it its liquid flexibility. However, water is very attracted to each other because water molecules is a very polar. This is because water’s electrons are closer to the oxygen atom due to the electronegativity of the oxygen atom being higher compared to the two hydrogen atom within the water molecule. This creates a hydrogen bond which is the strongest of the three intermolecular forces (beng london dispersion forces, dipole-dipole attractions,

With today’s science, light becomes more specifically perceived as a spectrum. The specific name for this spectrum is the electromagnetic spectrum, which contains many types of waves (NASA, Electromagnetic Spectrum). In Figure 2, the spectrum shows a variety of wavelengths with specific wavelengths classified by its length. The range of wavelengths humans can see wavelengths that are around 400 – 700 nanometers (nm) as colors while all other electromagnetic waves are simply blind to humans. The interesting classes for light that are used to measure are microwave and infrared light. The laser is

Before Einstein, Scientists believed that light waves travelled through a medium called ether. Einstein proved that ether was irrelevant and that light doesn’t travel through a medium. Einstein proved this by figuring out that the speed of light was constant, and in order for ether to be the medium light waves travel through, the speed of light would change depending on the observer. This discovery was one piece of the Specific Theory of Relativity.