Survey
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* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Describe and evaluate the advantages and disadvantages of different fuel sources. [6 marks] The Mark Scheme: Fossil fuels are non-renewable/release pollutants/contribute to acid rain Fossil fuels are readily available/low fuel costs/easily transported Nuclear fuels are non-renewable/produce radioactive waste/health risks due to exposure Nuclear fuels release no carbon dioxide or sulphur dioxide emissions/conserves fossil fuels/cheap to run. Biomass is renewable/does not increase surface carbon levels. Biomass still releases carbon dioxide Explain how passive solar heating can be used to heat a greenhouse. [6 marks] The Mark Scheme: • The sun is very hot • Visible light/short wavelength infrared energy directly from the sun • Transmitted through glass (transparent) • Absorbed by walls, floors and furniture in the room. • At night the walls, floors and furniture re-emit the energy as infrared with longer wavelengths as they are not as hot. • This radiation is not transmitted but reflected back into the room. What evidence exists to support the Theory that an Asteroid Impact was responsible for the extinction of the dinosaurs? [6 marks] The Mark Scheme: any 6 from below: • KT boundary: below this boundary there are fossils and above this boundary there are none [1] • Rare metal element Iridium which is only usually found in meteorites/asteroids is found in the KT boundary [1] • Shocked Quartz (in the KT boundary) shows a huge impact must have occurred with a large force [1] • Shocked Quartz and Iridium is not spread evenly but is thicker in the South east suggested an impact occurred here [1] • Yucatan Peninsula has horseshoe features that match the crater predicted and also there is shocked quartz and iridium found here [1] • Crater found on the Yucatan Peninsula – same size as was predicted [1] • Cenotes (large circular holes with underground lakes) in Yucatan Peninsula – these are found along fault lines but there are no known fault lines here so they must have formed from an impact [1] • Patterns of Cenotes match the shape of the crater found on the Yucatan Peninsula [1] • Can’t be coincidence that a large impact occurred and then suddenly the dinosaurs were gone – the impact must have caused the extinction [1] How is the evolution of our own star the Sun different from stars which are much larger? What will happen to the Sun when it runs out of fuel? [6 marks] The Mark Scheme: any 6 from below: • When our own star, the Sun, runs out of fuel it will go on to form a red giant [1] • More massive stars will go on to form red super giants [1] • The Sun will emit it’s outer layers as a planetary nebula [1] and then be left as a white dwarf [1] which will cool to form a black dwarf [1]. • A more massive star will erupt as a supernova [1] and then either form a neutron star [1] or a black hole [1]. Describe how the moon was formed. [6 marks] The Mark Scheme: • Earth and a second smaller planet (Thea) collided. • The force of the collision was enough to nearly destroy both planets. • The iron of both planets was dense and became concentrated into Earth’s core. • The less dense rocks orbited Earth in an accretion disc. • These rocks clumped together to form the Moon. • The evidence is that there is no iron on the moon and that it contains the same oxygen compositions as Earth. Explain the evidence that exists for the Big Bang. [6 marks] The Mark Scheme: • universe is finite in size as shown by the finite numbers of stars. • light from galaxies shows red shift • correct explanation of red-shift • those galaxies moving away fastest/further away show the most red shift • the remnants of the Big Bang can be shown as the Cosmic Microwave Background Radiation • statement relating to the volume of supporting evidence and agreement from scientists in both theoretic and experimental work.