Lesson 3.2 Light PDF

Lesson 3.2: Regions of Visible Light  REVIEW OF THE PREVIOUS LESSON… 1 identify the components of visible light; 2 discuss the hierarchy of colors in relation to energy; 3 explain the bending of colors according to their wavelengths and frequencies  Light is a form of energy th...

Lesson 3.2: Regions of Visible Light  REVIEW OF THE PREVIOUS LESSON… 1 identify the components of visible light; 2 discuss the hierarchy of colors in relation to energy; 3 explain the bending of colors according to their wavelengths and frequencies  Light is a form of energy that allows you to see the things around you. The components of the electromagnetic spectrum are described in terms of the quantities such as wavelengths (λ) measured in meters(m)or nanometers (nm), frequency (f) in per second or hertz (Hz), and photon energy (E) in electron volts (ev)unit.  The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. It provides a way of categorizing the vast array of electromagnetic waves that occur in the universe, from the lowest frequencies used for radio communication to the highest frequencies that ionize atoms. Electromagnetic waves are created as a result of vibrations between an electric and magnetic field. Frequency- how many EM waves is passed in a given point in a second. It is measured in Hertz (Hz). 1 waves per second is 1 Hz Amplitude—distance between the resting position and the Wavelength maximum displacement - distance of the wave from one wave to another On the leftmost end of Figure 3.4 are the waves with the lowest energy and long wavelengths but short frequencies known as the radio waves. They are commonly found in signal towers and antennas. Following them are the microwaves, the infrared waves, the visible light, the ultraviolet radiation, X-rays, and, finally, the gamma rays, which have the highest energy but with the shortest wavelengths. In the spectrum, you can see that the shorter the wavelength, the higher the frequency and the photon energy of the component radiation. It is important to note that the higher the energy of a radiation is, the more dangerous it is to the living cells.  The refraction or bending of white light in the prism is related to many common phenomena that are observable in our everyday lives. The appearance of rainbows start with the light rays from the Sun hitting the raindrops. When the rays enter a water droplet, light gets reflected and then refracted, which causes the splitting of light into different colors.  Mirage, a deceptive appearance of a distant object, is often observed on a very hot day. An illusion that looks like a sheet of water or a shiny mirror commonly seen when driving down a hot roadway, mirage is formed due to the refraction of light rays when the surface temperature and the air above is warmer than the air up in the atmosphere. The twinkling of the stars. When light rays enter Earth's atmosphere, each ray gets refracted as it passes through the different layers. Since the temperature and density of atmospheric layers are different, the bending of the light rays is unstable, and that gives the twinkling movement that is often seen in the dark sky.  TYPES OF WHITE LIGHTING: Incandescent fluorescent Neon sodium vapor tungsten-halogen light bulbs.  Thomas Edison is credited for developing a successful lighting system known as the incandescent light bulb. Once an electric current passes through the filament, it starts to heat up until it glows. It starts giving off the lower frequency light colors, such as red and orange. The more it gets hot, the higher frequency light waves are given off until it produces violet light. All these colors get combined, producing a white light.  Light is a form of an electromagnetic wave. It is measured in terms of wavelength, frequency, and photon energy. The colors of the visible light are red, orange, yellow, green, blue, indigo, and violet (ROYGBIV). Light can be produced through different types of lighting such as incandescent, fluorescent, neon, sodium vapor, and tungsten-halogen light bulbs. 1. What is the type of wave that has the lowest frequency and the longest wavelength? 2. How are energy and frequency related to each other? 3. What color in the visible light bent the most? The least?