P1 0.0 / 5 ? PhysicsEarth in spaceGCSEOCR Created by: Hattie BarnettCreated on: 06-05-17 12:31 What are three things that orbit the sun other than planets? Comets, dwarf planets, asteroids, dust 1 of 33 How old is the solar sytstem? About 5 hundred thousand million or 5 billion years old 2 of 33 Briefly explain the birth of a star... Dust and gas cloud collapses, nuclear fusion, huge light and heat 3 of 33 What are the two man elements found in the sun? Hydrogen and helium 4 of 33 What is a comet and how does it orbit? Balls of rock, ice and dust, have fails and orbit elliptically 5 of 33 How many stars are in the milky way? Thousands of millions 6 of 33 What is a light year? The distance light travels through a vacuum in a year 7 of 33 Is 80 000 light years in our galaxy? In (100 000 is out) 8 of 33 What does parallax show? The distance of stars 9 of 33 How does parallax work? Measures the array rent movement of a star from Earth at different times of the year- bigger movement= closer 10 of 33 What Is light pollution? Human light from earth lighting the sky making astronomical observations difficult 11 of 33 Why do we see stars as they were in the past? It takes light some time to reach us, depending on how far the object is 12 of 33 What is redshift? The changing in light wavelength of a galaxy (moves towards the red end of the spectrum) 13 of 33 What effect explains redshift? The Doppler Effect 14 of 33 What does redshift show? That other galaxies are moving away from us and further away galaxies are moving away faster 15 of 33 What is redshift evidence for? An expanding universe and the Big Bang 16 of 33 What other evidence is there for the big bang? Age of the oldest stars, cosmic background radiation, early elements 17 of 33 When is the Big Bang predicted to have happene? 14 billion years ago 18 of 33 Give two reasons it is difficult to predict the fate of the uinverse? It so big, we don't know how big, dark matter (invisible masses) 19 of 33 What do rocks on Earth show us? Age of Earth (must be older than oldest rocks), past climates etc. 20 of 33 What was Alfred Wegeners evidence for continental drift? Pangae (supercontinent fits together), rock, mountain and fossil correlation, materials found in areas the couldn't have been formed in 21 of 33 Why wasnt Wegeners Theory accepted at the time? Not enough evidence, not measurable, he was a meterologist not a geologist, contrasting theories (land bridge) 22 of 33 What new evidence proves continental drift? Magma rising and cooling into rock on the sea floor, magnetic field swaps so rocks are in different bands, oldest are furthest from the ridge 23 of 33 What are the different layers of Earth? Inner core, outer core, mantle, crust 24 of 33 What are the features of a p-wave? Longitudinal, through solids and liquids, fast 25 of 33 What happens to p-waves when they travel frm the outer core to the mantle and why? They refract due to a change of state (liquid-solid), wavelength changes so speed changes so direction changes 26 of 33 What are the features of an s-wave? Transversal, only travel through solids, slower 27 of 33 Do energy waves transfer material? No, only information and energy 28 of 33 What is a waves speed when it's wavelength is 2 and it's frequency is 12 24 (speed= wavelength x frequency) 29 of 33 What is a transversal wave? A wave that moves at 90 degrees to its direction of disturbance 30 of 33 What is a longitudinal wave? A wave that moves in the same direction as its direction of disturbance, has refractions and compressions 31 of 33 How can different scientists come to different conclusions from the same evidence? data fits both, creative through, different influences, not enough data 32 of 33 How do scientists decide between the theories? testing predictions and more evidence 33 of 33
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