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Cards in this deck (17)
- 1Key facts of the geocentric modelGreek astronmers believed that the sun, moon, planets and stars all orbited the Earth in perfect circles.
- 2Key facts of the heliocentric modelIn the 1600's they replaced the geocentric model with the heliocentric model. The helicentric model states that the Earth and all planets all orbit the sun, which is at the centre of the universe
- 3Galileo's observations- This proved the geocentric model was wrongGalileo was observing Jupiter by using a telescope when he saw 3 stars in a line near the planet. When he looked again the next evening, he saw these stars has moved in the wrong direction in the night sky. After a week a 4th star appeared. Afterwards he realised that the 4 objects were not stars they were moons orbiting Jupiter.
- 4What do all waves have? Just remember FAWS!!!Frequency, Amplitude, Wavelength and Speed
- 5What is wavelength?it is the distance from one peak to the next
- 6What is frequency?It is how many complete waves there are per second (passing a certain point) Is measured in hertz.
- 7What is amplitude?It is just the height of the wave (from the mid-line to peak)
- 8What is speed?Well...how fast it goes
- 9One THING important to remember is that waves transfer energy and information - without transferring matter.
- 10There are 2 formulas for wave speed that you NEED to knowSPEED (m/s) = FREQUENCY (Hz) X WAVELENGTH (m)
Wave speed (m/s) = distance(m)/time(s) - 11Tranverse wavesMost waves are tranverse:vibrations are at 90 degrees to to the direction of travel of the wave
1. Light and all other EM waves
2. S-waves
3. Waves on strings and springs
4. Ripples on water - 12Longitudinal wavesThe vibrations are along the same direction as the wave is travelling
1. Sound and ultrasound
2. P-waves
3. A slinky spring when you push and pull the end - 13Waves can be reflected...When a wave hits a boundary between one meduim and another some of its energy is reflected, this is why sometimes we see our reflection in puddles.
The angle of reflection is the same as the angle of incidence. - 14Waves can be refracted...EM waves travel more slowly in denser media. Sound waves travel faster in denser substances.
1. If the wave hits the boundary 'face on' it slows down but carries on in the same direction. 2. But if a wave meets a different medium at an angel, this part of the wave hits the denser layer first and slows down... - 15'Bending effect' experimentGet something straight, like a pencil and hold it partly submerged in a fish tank or in a glass of water will do.
- 16What is a real image?it is where the light from an object comes together to form an image on a 'screen'.
- 17What is a virtual image?Is when the rays are diverging, so the light from the object appears to be comng from a completely different place
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- Physics Flashcards on Untitled, created by megm on 02/01/2014.
- Created by
- megm · Jan 2014
- Updated
- Feb 19, 2016
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