Analysis of our Solar System
Analysis of our Solar System On a hot summer night, as you are sitting outside enjoying the evening, you tilt your head back and look into the night sky. You begin to wonder what is really out there? How far away are the stars? Are they stars or are they planets? We live in a part of the night sky called the "Milky Way Galaxy." Our galaxy can be seen with the naked eye on a clear summer night. It resembles a ribbon stretched across the night sky. During the summer is when the Milky Way is at its fullest with the stars so clustered together they look like one white mass. Our galaxy is a gigantic agglomeration of stars and planets whose numbers will probably never been known. Currently we estimate this number to be about thirty billion. Scientists have estimated that the radius of our galaxy if it were to be travelled, would take us about fifty thousand light years and the thickness to be about fifteen to twenty light years. We live in small part of the Milky Way Galaxy, which is referred to as a solar system. Our solar system is made up of nine planets and 31 moons, which orbit the centre of galaxy. At the centre of our galaxy is our Sun, which is approximately twenty-five thousand light years from our solar system. These nine major planets in order from the centre are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. Mercury is the planet
Experiment to Investigate which Factors Affect the Strength of an Electromagnet
Experiment to Investigate which Factors Affect the Strength of an Electromagnet Introduction An electromagnet is a magnet made of a solanoid with coils of wire around it. Aim To investigate which factors affect the strength of an electromagnet. Predictions I predict that the voltage, the amount of coils and the material of the solanoid can affect the strength of a magnet. I also predict that adding more coils increases strength. See domain theory. The Domain Theory The domain theory is that all the atoms point different ways in a piece of iron. When the piece of iron is magnetised all the atoms in the iron point to north. Variables The variables are the number of coils and the strength of the magnet. The number of coils I will change is in the independent variable and the strength of the magnet is the dependent variable. What I Intend to do I intend to investigate which factors affect the strength of an electromagnet. I intend to keep the voltage the same throughout the experiment I'm going to keep adding coils to the solanoid and find out how many paper clips it attracts. Apparatus Power Supply DC 0 - 13v demagnetising solanoid Connecting wires with plugs Crocodile clips Insulating wire (approximately 1m) Nail (soft iron) Heat proof mat Stand and clamp Paper clips Circuit Diagram Preliminary Experiment In the preliminary experiment I will check the
Resistance of a wire coursework. In my experiment I shall be using different types of wires with various lengths and widths. Through these I shall be testing the resistance which is caused by electrons.
Coursework: Resistance of a wire Introduction: I plan to do an experiment on the resistance of a wire. In my experiment I shall be using different types of wires with various lengths and widths. Through these I shall be testing the resistance which is caused by electrons. The electrons lose energy as they try to move past atoms. The effects are as follows: . The current is reduced and energy slows them down. 2. The potential difference of the electricity in the wire increases as it loses energy. 3. The wire is heated up by the energy that is lost from the electrons. A correlation between the length and the width of the wire is that the longer and wider the wire is, the more atoms there are. The resistance is larger wires should be higher. You can calculate the resistance by using Ohms law. This is the equation for Ohms Law: Resistance (R) = Voltage (V) / Current (I) This equation can then be rearranged to give voltage or current. Variables: Temperature: Atoms in the wire will vibrate as the temperature increases. The vibrations increase along with the temperature. This makes it more difficult for the electrons to avoid the particles in the wire. This causes the resistance to increase as the electrons spend more energy in collisions or trying to avoid atoms. Length: The longer the wire is, the more atoms there will be for the electrons to pass. This makes
Physics research study - vehicle safety and braking distances
Physics Write up .) Thinking Distance * Thinking distance - It takes time for a driver to react to a situation. During this reaction time the car carries on moving. The thinking distance is the distance travelled in between the driver realising he needs to brake and actually braking. * Braking distance - The braking distance is the distance taken to stop once the brakes are applied. The thinking distance and stopping distance add together make the stopping distance the stopping distance is how far you went before you finally stopped. The stopping distance is your thinking distance and stopping distance added together. The formula for working out the stopping distance is: Stopping distance = thinking Distance + braking distance 2.) There are variety of factors that affect the thinking distance one of the main factors is tiredness. Tiredness increases the breaking distance because when you are tired Your brain thinks slower and you will not be able to apply the brakes as quickly. Another factor that increases thinking distance is being under the influence drugs or alcohol this has been a huge economic issue for the government they have spent millions of pounds promoting the awareness of drunk driving (40% of all traffic fatalities are because of alcohol And to combat this they have introduced drinking limits. Being under the influence - even legally -
How safe are Mobile phones?
Introduction Mobile phones are becoming an essential business tool, a popular means of communication. In my report, I will be talking to you about mobile phone safety, then I will come to a conclusion based on my evidences and statistics. Disadvantages Mobile phones have numerous advantages but they also bring some disadvantages. * Effects on health The radiations of mobile phones are causing serious health hazards to the users. The mobile phone users are more prone to ear defects, headaches and blurring of vision1. This source is reliable because it is from the BBC website and the BBC website is not biased. It is valid because the article was published in 2005. This was a Swedish study carried out in 2002. Altogether 1249 people were surveyed, so it is reliable. SAR values are an indication of how much heat is absorbed into the head. The more the value, the more heat absorbed. This graph shows the top 10 SAR values in Europe for mobile phones2: Manufacturer Model SAR Rating W/Kg Sony Ericsson T650 .80 Sony Ericsson W880i .45 Nokia E51 .40 Sony Ericsson W950i .35 Sony Ericsson Z610i .32 Sony Ericsson K810i .31 Sony Ericsson W610i .31 Sony Ericsson W660i .27 Sony Ericsson K550i .25 LG & Nokia KU250 + N5700 .24 This graph shows that the phone with the highest SAR value in Europe is the Sony Ericsson T650. The information collected has
Rutherford's Alpha Particle Scattering Experiment:The discovery of the Nucleus...
Rutherford's Alpha Particle Scattering Experiment: The discovery of the Nucleus... Rutherford was the world leader in alpha-particle physics. In 1906, at McGill, he had been the first to detect slight deflections of alphas on passage through matter. In 1907, he became a professor at the University of Manchester, where he worked with Hans Geiger. This was just a year after Rutherford's old boss, J. J. Thomson, had written a paper on his plum pudding atomic model suggesting that the number of electrons in an atom was about the same as the atomic number. (Not long before, people had speculated that atoms might contain thousands of electrons. They were assuming that the electrons contributed a good fraction of the atom's mass.) Rutherford's alpha scattering experiments were the first experiments in which individual particles were systematically scattered and detected. This is now the standard operating procedure of particle physics. Rutherford's partner in the initial phase of this work was Hans Geiger, who later developed the Geiger counter to detect and count fast particles. The experiment was conducted, as is shown below. Alpha particles were fired from a source (from within a lead "shield") at a sheet of thin gold foil (which had been beaten to about 400 atoms thick. A fluorescent screen was placed behind / around the gold foil. Every time an Alpha particle hit the screen
Astronomical observation
Astronomical observation .Describe the observed motion of the stars during one night. At first sight stars appear not to move in the sky, they are seen static by human eyes. However recently astronomers have found that the stars are moving at fast velocities through space. The reason why they appear not to be moving is that they are so far away from us, the closest star is Proxima Centauri, which is 40 million million kilometers far away. 2.Describe the observed motion of the sun in the sky each day, and how this varies over the year, at different latitudes. From the earth the sun is seen to rise in the east, arc across the sky, and set in the west. However this is only an apparent motion, which happens because the earth spins on its axis from west to east. The sun is seen to rise higher in the sky in summer than in winter. This occurs because the earth spin is tilted in space. As the earth circles in orbit around the sun during a year, a particular place on the surface is tilted more towards the sun at some times than at others. This brings about the season. The greatest tilt occur on about June 21 and December 21 every year. On June 21 the Northern Hemisphere is tilted most towards the sun, and it is mid-summer. On December 21 the Northern Hemisphere is tilted farthest away from the sun and it is mid-winter. This days are known as the Solstices. 3. Describe the
Ionisation smoke alarms use an ionisation chamber and a source of ionising radiation to detect smoke.
Smoke Alarms What Is It? A smoke alarm is a device that can detect smoke; alternatively it can also be called fire alarm systems or household detectors. The smoke alarm was created to detect fires and would consequently give a warning in the form of a signal or an alarm. Smoke alarms are fitted to the ceiling and are usually a very small disk shape size. There are two main types of smoke alarms. The first one and probably the more commercial and cheaper one is the physical process alarm (Ionisation). These are usually powered by a single disposable battery. The other main type of smoke alarm is photoelectric, which basically works by optical detection.[1] This report is on Ionisation smoke alarms. How Do They Work? Ionisation smoke alarms use an ionisation chamber and a source of ionising radiation to detect smoke. These are the more inexpensive ones however; one major disadvantage of ionisation detectors is that they are sensitive to very small particles of smoke. An ion is an atom with a positive or negative charge.[2] To ionise means to remove an electron from an atom and purposely create positive and negative ions. Inside the ionisation chamber is a tiny amount of americium 241.[3] The reason why americium is often used instead of other radioactive elements is that americium 241 has a very long half life of 432 years. It is a very good source of alpha particles. The
Friction Between two surfaces
A Level Physics Coursework Friction Between two surfaces In this coursework I hope to show that friction does exist between two surfaces and that there are two types of friction, static and sliding. To show this I will have a tray filled with a mass and pull it with a Newton mass and measure the force needed to start the tray to move and then the force at which the tray travels at a constant speed. I hope to find that the sliding friction is smaller that static friction. Then I will go onto the coefficients of friction by having a block on a slope and measuring the height at which the book starts to slide. Then from the data I can work out the angle-using trigonometry. The theories of friction are: When a single force is applied to an object of mass m, it will cause acceleration. This is described by Newton's Second Law, using the relation F = m x a with this equation, you can predict the acceleration given to the object by the applied force, or you can find the force if you know the acceleration. I have decided that I am not going to find the acceleration and therefore cannot find the force F applied. There are two types of friction static and sliding. Sliding friction is the frictional force, which exists between two adjacent surfaces, which are in relative motion, and is usually slightly less than the limiting frictional force between the surfaces. Static
Experimental Verification of Ohm's Law
Experimental Verification of Ohm's Law Apparatus * E.M.F Source - Battery of 2 X 1.5V Cells * Battery Holder * Switch * Variable Resistor (Rheostat) * Ammeter (preferably digital) * Voltmeter (preferably digital) * Sample of conductor to be tested (Nichrome wire) - 10cm * Connecting Wires * Crocodile Clips Procedure: * Choose the ranges of the ammeter and the voltmeter to suit the particular conductor to be tested. (e.g. 0-2V and 0-1A) * Set up the circuit as shown above. * Make sure that the voltmeter is connected in parallel across and the ammeter is connected in series with the conductor. * Ammeters and Voltmeters have terminals marked + and - which must be connected correctly to the battery. Only close the switch when you are sure that you have wired the circuit properly. * Close the switch and smoothly adjust the rheostat from minimum resistance to maximum resistance and at regular intervals note the meter reading and hence obtain a set of values from the two meters (at least 6). * Divide the Voltage by the current to get Resistance and tabulate the results in a table as shown below Current, I (A) Voltage, V (V) Voltage/Current , R (?) 0 0 - Current Reading 1 Voltage Reading 1 Current/ Voltage Current Reading 2 Voltage Reading 2 Current/ Voltage Current Reading 3 Voltage Reading 3 Current/ Voltage Current Reading 4 Voltage Reading
