Flashcards
Physics Core
Flashcards do conjunto (19)
- 1P1:T1 How has the structure of the solar system changed over time?1) Geocentric model- the sun, moon, planets orbit the Earth in perfect circles.
2) Heliocentric model- Earth, moon, planets orbit the sun which is at the centre of the universe.
3) Now the planets in our solar system orbit the sun, but he orbits are elliptical. - 2P1:T1 How have scientists use waves to find out information about our Universe?1)Scientists detect waves from objects in space. Objects like stars are huge, very hot and far away from us. They give out lots of visible light which is why we can see them.
2) We can see planets in our solar system because they reflect sunlight. - 3P1:T1 How has Galileo's observations of Jupiter provided evidence for the heliocentric model of the Solar System?Galileo was observing Jupiter using a telescope when he saw three stars in a line near the planet. When he looked again, he saw these stars had moved in the wrong direction. After a week, a fourth star appeared. These stars never moved away from Jupiter, he then realised that they weren't stars but moons orbiting Jupiter. This proved that not everything was in orbit around the Earth which proved the geocentric model wrong.
- 4P1:T1 What methods can be used to observe the Universe?1) The naked eye- stars, comets and planets were discovered this way. The naked eye is only useful for mapping their positions as they are so small and far away from us.
2) Telescopes- magnify images, so distant objects can be seen in more detail. You can also see objects that are far away from us. New objects have been discovered using telescopes and has helped us learn more about what the universe is made up of.
3) Photographs- photographs can be taken using telescopes. This allows you to zoom in and look at objects in more detail. This is useful as you can take pictures at different times to compare them and share your observations with others. You can see faint objects by allowing a long exposure time so that you can collect more light. - 5P1:T1 Explain how to measure the focal length of a converging lens using a distant object?1) Clamp the lens at one end of a track. Then clamp a piece of white card further down the track.
2) Set up this equipment near a window with the lens directed at a distant object, you should be able to see an image of the object on the piece of card. Turn off any lights in the room to make the image more visible.
3) Move the card along the track until the image is focused. When you've got the best image, clamp the piece of card in one place so it doesn't move.
4) Use a ruler to measure the distance between the centre of the lens and the card, this is the focal length. - 6P1:T1 How do you investigate the behaviour of converging lenses?1) A real image is where the light from an object comes together to form as image on a screen.
2) A virtual image is when the rays are diverging so the light from the object appears to be coming from a different place.
3) When you look in a mirror you see a virtual image of your face, because the object appears to be behind the mirror.
4) You can get a virtual image when looking at an object through a magnifying lens, the virtual image looks bigger and further away. - 7P1:T1 How do you investigate the use of converging lenses?1) Converging lenses are used to focus light: A converging lens is convex, it bulges outwards. It causes parallel rays of light to converge to a focus.
2) The axis of a lens is a line passing through the middle of the lens.
3) The focal point is where rays hitting the lens parallel to the axis all meet.
4) Each lens has a focal point in front of the lens, and one behind.
1) Distance from the lens affects the image: Put an object on the other side of the lens to the card.
2) Move the object away from the lens and move the card until you get a focused image of the object. The object should be well lit, but the screen shouldn't. Make a note of the distance from the object to the lens, and from the lens to the card. Do this a few times with the object at different distances from the lens. - 8P1:T1 Explain how the eyepiece of a simple telescope magnifies the image of a distant object?1) The rays of light from the real image enter the eye piece lens.
2) The lens spreads them out so they leave at a wider angle.
3) The light rays fill more of your retina; this makes the image looked magnified. - 9P1:T1 Do electromagnetic waves travel slower or faster in denser substances?Slower.
- 10P1:T1 Do sound waves travel slower or faster in denser substances?Faster.
- 11P1:T1 Describe how a reflecting telescope works?1) A large concave mirror collects the parallel rays of light from an object in space.
2) The larger mirror reflects this light onto a small second mirror placed in front of the large mirror's focal point.
3) The smaller mirror reflects the light through a hole in the centre of the large collecting mirror. A real image is formed behind the mirror.
4) A converging eyepiece lens is used to magnify this image. - 12P1:T1 Are waves reflected and refracted at boundaries between different materials?Yes.
- 13P1:T1 Explain how waves will be refracted at a boundary?1) Waves travel at different speeds in substances which have different densities.
2) When a wave crosses a boundary between 2 substances, it changes speed.
3) If the waves hits the boundary face on it slows down but carries on in the same direction.
4) But if a wave meets a different medium at an angle, the wave hits the denser layer first and slows down.
5) While another part of the wave carries on at a faster speed. Meaning the wave changes direction. - 14P1:T1 Explain what would happen if light shines on a glass window pane?1) Some of the light is reflected, but a lot of it passes through the glass and gets refracted.
2) As the light passes from the air into the glass, it slows down. This causes the light ray to bend towards the normal.
3) As the light reaches the glass to air boundary on the other side of the window, its passing into a less dense medium. So it speeds up and bends away from the normal.
4) The light ray that emerges on the other side of the glass is now travelling in the same direction it was to begin with, its been refracted towards the normal and then back again by the same amount. - 15P1:T1 Explain how waves will be reflected at a boundary?1) When a wave hits a boundary between one medium and another, some of its energy is reflected.
2) The angle of reflection is the same as the angle of incidence.
3) The light's reflected because of the change in density.
4) Whenever a wave reached a medium with a different density, some of the wave is reflected at the boundary. - 16P1:T1 What do waves do?Waves transfer energy and information without transferring matter.
- 17P1:T1 What is frequency, wavelength, amplitude and speed?1) Frequency- how many complete waves there are per second.
2) Wavelength- the distance from one peak to the next.
3) Amplitude- the height of the wave from the mid-line to the peak.
4) Speed- how fast it goes. - 18P1:T1 What is frequency measured in?Frequency- hertz
- 19—
Informações
- Descrição
- FlashCards sobre Physics Core, criado por Bobkay Bokay Kay em 27-12-2016.
- Criado por
- Bobkay Bokay Kay
- Visualizações
- 0
- Avaliação