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36 Cards in this Set
- Front
- Back
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What is a wave?
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A disturbance/movement that transfers energy through matter or space, without causing any permanent displacement
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What is energy?
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The capacity to apply a force over a distance.
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What is a force?
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A push or pull on an object
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What is rest position?
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The level of the water when there are no waves
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What is a crest?
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The highest point in a wave
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What is a trough?
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The lowest point in a wave
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What is a wavelength?
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The distance from crest to crest or from trough to trough.
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What is amplitude?
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The height of a wave crest or depth of a wave trough, as measured from it's rest position
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How is amplitude related to energy carried by the wave?
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The larger the amplitude, the greater energy transported.
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What is frequency?
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The number of repetitive motions, or oscillations that occur in a given time
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What is frequency measured in?
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Hertz (Hz), or cycles per second.
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What is an inverse relationship?
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When one value increases as the other decreases (e.g. long wavelengths=less frequency, short wavelengths=more frequency)
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Do water waves carry water?
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No, it carries energy, which makes the water move forward
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What is a medium?
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the matter the waves travel through (e.g. solid, liquid, gas)
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What happens in a transverse wave?
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Matter in the medium moves up and down perpendicular to the direction that the wave travels
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What happens in a compression wave? What is an example?
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Matter in the medium moves back and forth along the same direction the wave travels. Sound waves are compression waves.
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Do all waves need a medium to travel through? If not, what are some examples?
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No, visible light waves and radio waves don't medium. They can travel through space where there is no material.
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How do I calculate Hertz?
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frequency= cycles/seconds e.g. 26 swings in 6 seconds= 4 Hz
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What is a model?
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it is a way of representing something in order to understand it better and to make predictions
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What is the wave model of light? What is light anyway?
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it pictures light travelling as a wave. light is a type of wave that travels through empty space and transfers energy from one place to antoher (e.g. the Sun to the Earth)
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What is refraction?
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the bending or changing direction of a wave as it passes from one material to another
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What is sunlight?
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It is a white light. It is made up of waves with different wavelengths and frequencies.
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Why do different colours shoot out from a prism?
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because the prism refracts light the longer wavelengths are refracted less than shorter wavelengths, thus making different colours emerge
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Which colour has the shortest wavelength? Which one has the longest? (think of a arched rainbow)
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Red has the longest wavelength (700 nm) and violet has the shortest (400 nm)
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How did Sir Isaac Newton find out if colour picked up when light strikes a coloured object or not?
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He placed a prism in a room so a thin beam of white light could pass through it, making bands of colours emerge. Each band was refracted at a different angle. He thought that the colours were already in the white light, not the prism. It was just hiding.
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What is reflection?
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when a light wave strikes an object and bounces off.
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Why does a red shirt look black if it is placed in a dark room?
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Because it cannot produce it's own light and because there is no light present. It just absorbs whatever colour is around it, which is black.
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The additive primary colours are green, red and blue. What colour is made with:
Red+green? Red+blue? Blue+green? |
yellow. magenta. cyan
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what is light classified as?
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an electromagnetic radiation
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What is electromagnetic radiation?
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the transmission of energy in the form of waves that extend from the longest radio waves to the shortest gamma rays.
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What are radio waves?
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A type of electromagnetic waves that have the longest wavelenth and lowest energy and frequency of all the other waves.
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What are microwaves?
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waves that have the shortest wavelength and highest frequency of all the radio waves.
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What are Infrared Waves?
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a type of electromagnetic radiation that have a longer wavelength and lower energy and frequency.
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What are ultraviolet waves?
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a type of electromagnetic radiation that have a shorter wavelenth and higher frequency and energy. This energetic radiation allows your skin to make vitamin D (Sun) but overexposure to UV can result in skin damage
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What are x rays?
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a type of electromagnetic radiation that have a much shorter wavelength and higher energy and frequency than UV waves. Commonly used to photograph bones
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What are gamma rays?
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a type of electromagnetic spectrum with the highest energy and frequency and shortest wavelength. Used in radiation therapy to kill cancer cells.
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