GCSE Astronomy Revision Notes

TOPIC 1 EARTH, MOON AND SUN TOPIC 1.1 PLANET EARTH . What three features distinguish Earth from other planets in our solar system? * Liquid water, atmosphere, life . Explain how Raleigh scattering makes the sky appear blue. * When blue light hits oxygen and nitrogen in the atmosphere, it is absorbed and reemitted in any direction. This is due to the shorter wavelength of blue light compared to other colours, meaning that it is scattered more often than other colours, which pass through more easily. This is why the sun appears more orange at sunset – the light passes through more atmosphere, so more light is scattered, so only the most red light passes through, as all of the blue light is scattered. . Why is Earth’s atmosphere beneficial to humans? * The atmosphere keeps the Earth at a relatively warm temperature suitable for life. It also protects Earth’s surface from ultraviolet radiation. This is due to the ozone gas filtering out these rays. It contains oxygen and carbon dioxide, which are needed for life. . Name three causes of light pollution. * Shopping centres, floodlights, street lights, etc . Why is light pollution undesirable for astronomers? * It makes it difficult to see fainter stars and galaxies. . What shape is the Earth? * Oblate spheroid (squashed sphere). The diameter is greater at the equator than it is at the poles. . What is the

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  • Level: GCSE
  • Subject: Science
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My Project On Artificial Satellites.

INTRODUCTION Space Exploration, quest to use space travel to discover the nature of the universe beyond Earth. Since ancient times, people have dreamed of leaving their home planet and exploring other worlds. In the later half of the 20th century, that dream became reality. The space age began with the launch of the first artificial satellites in 1957. A human first went into space in 1961. Since then, astronauts and cosmonauts have ventured into space for ever greater lengths of time, even living aboard orbiting space stations for months on end. Two dozen people have circled the moon or walked on its surface. At the same time, robotic explorers have journeyed where humans could not go, visiting all but one of the solar system's major worlds. Unpiloted spacecraft have also visited a host of minor bodies such as moons, comets, and asteroids. These explorations have sparked the advance of new technologies, from rockets to communications equipment to computers. Spacecraft studies have yielded a bounty of scientific discoveries about the solar system, the Milky Way Galaxy, and the universe. And they have given humanity a new perspective on the earth and its neighbors in space. The first challenge of space exploration was developing rockets powerful enough and reliable enough to boost a satellite into orbit. These boosters needed more than brute force, however; they also

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In this experiment I aim to find out how the force and mass affect acceleration. I shall do this by setting up an experiment involving a ticker tape timer and trolley.

Method In this experiment I aim to find out how the force and mass affect acceleration. I shall do this by setting up an experiment involving a ticker tape timer and trolley, to keep the experiment as fair as possible I will only change one variable at a time. For the first part I will only vary the force (see fig. 1) in difference weights of 1N, 2N, 3N and 4N. In order to keep the friction acting on the trolley constant I will make the ramp which the trolley is on at the exact angle so it would keep moving at constant speed if I pushed it, this simulates no friction. Also I will keep the mass of the trolley constant by weighing it on a top pan balance. Finally the ticker timer was kept at constant time intervals. Aswell as varying the force I decided to vary the mass of the trolley in masses of an extra; 100g, 200g, 300g and 400g. However as in the first part I have to keep the other variables constant, the force pulling on the trolley must stay at 1N and in the same way as before also the friction and time intervals. Another thing that I would usually take into consideration is that the experiment should be repeated to give better results, however this is not important because the ticker timer and trolley give very accurate results. After setting up the apparatus to give fair results I will carry out four sets of ticker timers for the force and then for the mass of the

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  • Subject: Science
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Resistance of a Wire Investigation

FIRST Before starting my coursework I have decided to choose a factor that will affect the resistance of a wire. I shall do this by going through all of the factors that affect the resistance of a wire and how I would measuring each factor to find out which would be the most effective and easiest factor to measure. Below is a list of factors and reasons why they affect the resistance of a wire. From this list of factors I shall only pick one factor to investigate. To explain the how the factors would affect the resistance of a wire I have drawn a diagram to show how resistance occurs. GAP To chose which factor I am going to investigate I am going to consider how I would measure each factor and which factor would be the best and easiest to record. To measure the wire width I would use different widths of the same length and same material of wire. To record the difference in widths I would use the same voltage and measure the resistance for each thickness. Although it would be easy to obtain and record the data the graphs that I would be able to draw up would not be interesting. For the temperature of the wire I would not be able to carry out a fair test because it is extremely difficult to produce and control the range of temperatures needed without the correct equipment. If I chose to measure the difference in the resistance in different materials I would chose a number of

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An in Investigation into the Resistance of a Wire.

An in Investigation into the Resistance of a Wire Aim: To investigate the factors affecting resistance There are four main factors which affects the resistance and they are: > The material > The cross-sectional area (thickness) > The length > The temperature But in this investigation I am only going to investigate in the factors length and cross sectional area Background Information Electricity cannot be seen but you can see the effect electricity has. It can: > Make things hot-as in the heating element of an electric fire > Make things magnetic-as in an electromagnet > Produce light-as in a light bulb > Break down certain compounds and solution-as in electrolysis In a nutshell, electricity is very good at transferring energy. To understand this, a simple model of what happens in electrical circuits can help. If an electrical circuit is made using a battery and a lamp, the battery can be thought of as pushing electrical charge round the circuit to make a current. The battery also transfers energy to the electrical charge. The voltage of the battery is a measure of how much 'push' it can provide and how much energy it can transfer to the charge. Scientists now know that electric current is really a flow of electrons. The electrons actually flow around the circuit from negative to positive. Unfortunately, although early scientists knew that there must be

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  • Subject: Science
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Investigating the amazingness of theBouncing Ball!

Physics A2 Coursework Investigating the amazingness of the Bouncing Ball! In this investigation I will lead you through my experiments and findings on the decaying bounce of balls. From this investigation I want to have worked out the effect of temperature change on the decaying bounce of a ball. However, at first I will have to choose suitable variables for this experiment. First of all I had to distinguish a method for measuring the heights reached by the bouncing ball. My initial idea was to have a white ball bounce against the backing of a grided black board, so as the ball bounced I'd mark out where the ball bounces. Using a light gate the second time, I'd make sure that the ball did indeed reach that point. However, the ball wouldn't bounce to the exact same height every time, as the ball may bounce sideways and so the height reached would change. Where I mark out the height depends on my eye level and how quick I am to mark out this height may be delayed by i.e./ how tired I am at the time. This method is very prone to error. Another method that may have worked would be to have metal claws, interlocking however not making contact ie. like a grid, but with a charge running through them. A metal or a ball wrapped with tin foil or just a thin layer of metal on the outside of a ball would be bounced onto this grid. Each time the metal plated ball bounces

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To investigate how the length (mm) and the cross-sectional (mm2) area of a wire affects its resistance (ohms).

GCSE COURSEWORK PHYSICS : RESISTANCE OF A WIRE Coursework Coursework Owner : Abu Shoaib Date Submitted : 7 November 2003 Form : 5A TABLE OF CONTENTS . PLAN 3 .1. Aim: 3 .2. Background knowledge: 3 .3. Apparatus: 3 .4. Safety: 4 .5. Variables: 5 .5.1. RESISTANCE (OF ENTIRE CIRCUIT) 5 .5.2. RESISTANCE (OF RHEOSTAT) 5 .5.3. LENGTH 5 .5.4. CROSS-SECTONAL AREA 6 .5.5. SUBSTANCE 8 .5.6. TEMPERATURE 8 .6. Observations to be made: 9 .7. Theory: 10 .8. Method: 12 .9. Prediction: 13 .9.1. LENGTH: 14 .9.2. CROSS-SECTIONAL AREA: 14 .10. Variables table: 15 .11. Preliminary work: 15 2. OBTAINING EVIDENCE 16 2.1. Preliminary Results: 16 2.1.1. LENGTH: 16 2.1.2. CROSS-SECTIONAL AREA: 16 2.2. Length: 17 2.3. Cross-sectional area: 19 3. ANALYSIS 21 3.1. THEORY/HYPOTHESES: 21 3.2. LENGTH: 22 3.3. CROSS-SECTIONAL AREA: 23 3.4. CONCLUSION: 24 4. EVALUATION 26 4.1. LENGTH: 26 4.2. CROSS-SECTIONAL AREA: 28 4.3. OVERALL EVALUATION: 29 5. EXTENSION PLAN 30 5.1. Aim: 30 5.2. Apparatus: 30 5.3. Safety: 31 5.4. Theory: 31 5.5. Prediction: 33 6. GRAPHS 34 - 68 . PLAN .1. Aim: To investigate how the length (mm) and the cross-sectional (mm2) area of a wire affects its resistance (ohms). .2. Background knowledge: Electricity, or more specifically, the flow of electrons carrying an electrical charge through a metallic conductor is known as an

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An experiment to find the resistivity of nichrome

An experiment to find the resistivity of nichrome A. Planning Plan of the method to be used: - The resistivity of nichrome can be determined using the equation ??=?RA/L Where: R:- Is the resistance of the wire in ?"ohms" and can be determined using the equation R=V/I where "V" is voltage in volts and "I" is current in Amperes. L:- Is the length of the nichrome wire used in metres. A:- Is the cross-sectional area of the wire in metres square and can be determined using the equation A= ??d2 where "d" is the diameter of the wire. If I plot a graph of length on the x-axis against resistance on the y-axis. From the relation R = ? L /A which corresponds to the st. line equation ? y=mx the graph should be a st. line passing through the origin where "m" is the gradient of the st. line graph and corresponds to ?/A. Since the cross-sectional area of the wire can be found by knowing it's diameter. Therefore the resistivity of nichrome can be calculated. ? Diagram of the circuit used in this experiment List of the apparatus used: - - Power pack supply of 4V 2-A variable resistor 3-A full scale deflection ammeter with a measuring range of 0-1 A 4-A digital voltmeter with a measuring range of 0-5 V 5-P, Q represents terminal blocks. 6-Circuit wires 7-PQ=Nichrome wire 8-A meter ruler 9-Michrometer screw-gauge 0-Sellotape Detailed method: - I set up the circuit

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Discover the factors affecting resistance in a conductor.

Introduction The aim of this investigation is to discover the factors affecting resistance in a conductor. I will use what I believe to be the most effective method and experimentation in order to come to a fair conclusion and accurate evaluation. Secondary sources will be used in order to confirm any theories or motives that I may use, and all conclusions will be explained using scientific theory or the results from the experiments that will be carried out. Each experiment will be completed safely, and using the best of my scientific knowledge. Results will be arranged neatly and analysed carefully. At the end of this investigation I would like to have discovered whether the conductor obeys Ohms Law, in reference to a sound prediction in relation to my conclusion and evaluation. Basic Plan As already said, I am going to discover the relationship between the length (and diameter) of carbon putty and the resistance. This can then be plotted on a graph, using the two factors of voltage and current. To discover the relationship between the length of carbon and its resistance, the putty will be placed in the circuit at different lengths, and the current and voltage will be recorded at each of these lengths, and then the following equation can be used: Resistance = Voltage OR R = V Current I Therefore the resistance can be discovered, however the unit of

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  • Subject: Science
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Resistance and Wires

21st Century Additional Science Written Science Experiment - Resistance and Wires How is the resistance of nickel-chrome wire affected by its length and diameter? How is the resistance of nickel-chrome wire affected by its length and diameter? Introduction This investigation determines how changing the length of Nickel-Chrome (nichrome) wires, when passing an electrical current through them, affects their resistance. It also determines how resistance is affected by a change in the diameter of the wire used. Resistance is "the property of failing to conduct electrical or thermal energy". Resistance is a force which opposes the flow of an electric current around a circuit so that more energy is required to push the charged particles around the circuit. The circuit itself can resist the flow of particles if the wires are either very thin or very long, e.g. the filament across an electric light bulb. Resistance is measured in ohms. A resistor has the resistance of one ohm if a voltage of one volt is required to push a current of one amp through it. George Ohm discovered that the emf (electromagnetic force) of a circuit is directly proportional to the current flowing through the circuit. This means that if you triple one, you triple the other. He also discovered that a circuit sometimes resisted the flow of electricity. He called this, resistance. He then came up with a

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  • Level: GCSE
  • Subject: Science
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