Chapter 2 Lesson 3 Light from Space PDF

# Unit 1: Chapter 2 - Stars and Light ## Lesson 3: Light from Space ### Vocabulary - **Electromagnetic Wave:** waves that are created as a result of vibrations between an electric field and a magnetic field. ### Different Types of Electromagnetic Waves - Microwaves, radio waves, and the light w...

# Unit 1: Chapter 2 - Stars and Light ## Lesson 3: Light from Space ### Vocabulary - **Electromagnetic Wave:** waves that are created as a result of vibrations between an electric field and a magnetic field. ### Different Types of Electromagnetic Waves - Microwaves, radio waves, and the light waves from a lightbulb are a type of electromagnetic radiation. - Like all waves, electromagnetic waves transfer energy. ### Different Types of Electromagnetic Waves - Light waves have the same properties as other waves. - You can measure the wavelength, amplitude and frequency of light. - Wavelength and frequency correspond to the different types of electromagnetic waves. - Amplitude corresponds to its brightness. ### Different Types of Electromagnetic Waves - Electromagnetic radiation can transfer information. - Radio waves broadcast information many miles away. - Electromagnetic waves travel from celestial objects in to space and down to Earth. ### Types of Electromagnetic Radiation | Wave | Wavelength | | ---------------------------------- | ---------------- | | Radio | Long | | Microwaves | Short | | Infrared | Very Short | | Visible light | Shortest | | Ultraviolet | Extremely short | | X-rays | Extremely short | | Gamma rays | Extremely short | - Radio is used to broadcast radio and television. - Microwaves are used in cooking, radar, telephone and other signals. - Infrared transmits heat from the sun, fire, and radiators. - Visible light makes things able to be seen. - Ultraviolet is absorbed by the skin, used in fluorescent tubes. - X-rays are used to view inside of bodies and objects. - Gamma rays are used in medicine for killing cancer cells. ### Reflection, Refraction, and Absorption - When radiation interacts with matter, it can reflect, refract, or absorb. ### Absorption - Absorption occurs when a wave enters a new medium and tje medium's molecules vibrate. The object absorbs the incoming light. - Because light carries energy, this causes the energy of the object to increase. - This is how a microwave heats your food! - This is also why sunlight feels warm on your skin. ### Reflection - Reflection occurs when light bounces off an object. - The law of reflection says that light will leave the object at the same angle it struck the object. - At any given moment, all objects are both absorbing and reflecting light. - Though all objects reflect light, not all objects produce smooth reflections. - Non-reflective objects produce diffuse reflection. Because the microscopic surface is very rough, light is reflected in many different directions. - Smooth surfaces such as glass reflect light in a single direction. This produces a clear image. ### Transmission - Transmission occurs when light moves through an object. Both glass and water allow light to pass through them. ### Refraction - Refraction occurs when light moves from one medium to another, and the path of light bends. This can cause the resulting image on the other side to change. - Lenses in eyeglasses, microscopes, and telescopes use refraction to improve the quality of an image.