Question | Answer |
Electromagnetic waves | waves that consist of electric and magnetic fields that vibrate at right angles to each other |
Does light have to travel through matter? | No |
Do sound waves have to travel through matter? | Yes |
Do water waves have to travel through matter? | Yes |
How do electromagnetic waves travel? | They travel around and change electric and magnetic fields |
Radiation | transfer of energy as electromagnetic waves |
How long does it take light to travel from the sun to Earth? | 8.3 minutes |
Electromagnetic spectrum | All of the frequencies or wavelengths of electromagnetic radiation |
Infrared waves | Below red |
Reflection | Bouncing back of a ray of light, sound, or heat when the ray hits a surface that it does not go through. |
A firefly is an example of a ________. | luminous object |
Absorption | In optics, the transfer of light energy to particles of matter. |
Scattering | An interaction of light with matter that causes light to change its energy, direction of motion, or both. |
Why is the sky blue? | Because of the scattering from the lights. |
Refraction | The bending of a wave as the wave passes between two substances in which the speed of the wave differs |
On page 78, why does the cat see the fish up close and the fish see the cat far away? | Because the fish is in the water. Since the cat is looking into the water, the fish looks closer to him. |
How does white light get separated into a rainbow | It goes into the colors of visible light by refraction |
Diffraction | change in the direction of a wave when the wave finds an obstacle or an edge, such as an opening |
Interference | Combination of two or more waves that results in a single wave |
Transmission | Passing of light or other form of energy through matter |
Transparent | Describes matter that allows light to pass through with little interference |
Translucent | describes matter that transmits light but that does not transmit an image |
Opaque | describes an object that is not transparent or translucent |
Primary colors of light | Red, blue, and green |
Why are red, green, and blue primary colors of light | they combine to make white light |
What does the law of reflection show? | That it is equal to the angle of reflection |
Incidence | The arrival of beam of light at a surface |