REsearch into the dangers of sunbeds.
6/20/2011 Title: (Physics) Name of student: Therese Anasthasia Seforah Name of school: G.M.D Atchia State College Name of supervisor (Teacher): H.Dulgeet Subject: 21st Century Science 5131 ________________ Introduction I will be conducting this case study in order to find out evidence about whether sunbeds cause only skin cancer or not. As the pressure of young people is to become perfectly preened and tanned steadily increases, more and more turn to sunbeds as a way to find that perfect summer glow. However, the darker the sides to this story is the soaring numbers of skin cancer, are they paying for their vanity, or is it a pure coincidence? – Because in my opinion, it is a currently pressing issue, so many people today are turning to sunbeds, and with the sunbeds they are becoming stronger and stronger, are we killing ourselves? I will find several pieces of information to support each theory and then show my conclusion. In the finding of these pieces of evidence I will be checking of how reliable it is and then I will come to my conclusion. Background Science Information In order for my arguments to be explained and to be understood, background information is important to be explained so as to help you to understand clearly the theory about my experiment on sunbeds. In other words, I will help you by providing diagrams, pictures and scientific reviews of
Soil water content in relation to species diversity in a Pingoe.
Soil Water Content in Relation to Species Diversity in a Pingoe Introduction Fouldon common is situated in the east of England near Norfolk. The area has been classified a Site of Special Scientific Interest as it is a rare habitat known as Ancient Chalk grassland. It is because of the large amounts of chalk in the ground that the soil is alkaline and has a PH of around 8.0. There are very few areas of natural grassland present to day as most are used for agricultural purposes or have developed in to woodland. There are two main reasons why this is not the case at Fouldon common, the first is the presence of pingos and the second is grazing. In past years the people who lived in Fouldon had gazing rights this means that they were able to use the land for grazing there own animals such as sheep. Due to agricultural advances there has been a decline in this from the beginning of the twentieth centaury. The other main source of grazing at Fouldon common was from Rabbits. Unfortunately due to the Myxomatosis epidemic in the 1950's the population of rabbits at Fouldon common like many other places across the British Isle has declined. This then resulted in a serious drop in the amount of grazing at Fouldon causing large amounts of the grassland to develop into scrubland. Now under new ownership precautions to insure the preservation of the common have been put in place, this
Resistance Investigation
Resistance Investigation Aim An electronics factory needs resistors of 5 ohms and 15 ohms for a new electrical device. My task is to investigate how the resistance of a piece of wire depends on length and to find the length of the wire needed to make the required resistors, using only 4 volts. Introduction/Planning A selection of different wires made from constantan and nichrome and the usual laboratory apparatus will be available for me. Wire A - Constantan wire of approximate diameter 0.3mm Wire B - Constantan wire of approximate diameter 0.4mm Wire C - Constantan wire of approximate diameter 0.3mm A constantan is an alloy whose resistance stays fairly constant when it becomes hot. In fact the resistance changes by less than 0.5% even when the temperature rises by a few hundred degrees. Nichrome, along with other metals, is an alloy whose temperature does change appreciably when it becomes hot. Before starting my coursework, I have to find the variables in the experiment, safety aspects etc. I found that a number of things affect the resistance of a wire. Below is a list of factors and reasons why they affect the resistance of a wire. From this list of factors I have to make sure that these factors remain constant or excluded from the experiment. We are only investigating length but the other variables may change our outcomes. In electricity, resistance is the
Factors affecting Resistance of a wire
Factors affecting Resistance In preliminary work, I wanted to find out which factors affect resistance. In some research I found that there were four factors. The four factors of resistance are: * Temperature: If the wire is heated up the atoms in the wire will start to vibrate because of their increase in energy. This causes more collisions between the electrons and the atoms as the atoms are moving into the path of the electrons. This increase in collisions means that there will be an increase in resistance. * Material: The type of material will affect the amount of free electrons, which are able to flow through the wire. The number of electrons depends on the amount of electrons in the outer energy shell of the atoms, so if there are more or larger atoms then there must be more electrons available. If the material has a high number of atoms there will be high number of electrons causing a lower resistance because of the increase in the number of electrons. Also if the atoms in the material are closely packed then the electrons will have more frequent collisions and the resistance will increase. * Wire length: If the length of the wire is increased then the resistance will also increase as the electrons will have a longer distance to travel and so more collisions will occur. Due to this the length increase should be proportional to the resistance increase. * Wire
The Flywheel as an Alternative Energy Storage Device for Electric Vehicles (EV): Problems Associated with the Implementation, and Possible Solutions
International Baccalaureate Extended Essay Physics The Flywheel as an Alternative Energy Storage Device for Electric Vehicles (EV): Problems Associated with the Implementation, and Possible Solutions Candidate Name: Keith Lau Year 1999 IB Candidate Number: D0637036 Word Count: 3987 THE FLYWHEEL AS AN ALTERNATIVE ENERGY STORAGE DEVICE FOR ELECTRIC VEHICLES (EV): PROBLEMS ASSOCIATED WITH THE IMPLEMENTATION, AND POSSIBLE SOLUTIONS 1 ABSTRACT 2 INTRODUCTION 2 My research question 2 MAXIMIZING THE ENERGY STORED IN THE FLYWHEEL - IN THEORY 2 Why a flywheel is desirable to have a high angular velocity instead of a very large moment of inertia 2 The maximum angular velocity of the flywheel 2 The maximum energy stored 2 What materials would be feasible in this application 2 THE LEAKAGE OF ENERGY STORED 2 How friction prevents flywheels from being efficient 2 Magnetic bearing - and its workings 2 THE GYROSCOPIC EFFECT 2 The gyroscopic effect of the flywheel 2 What could be used to eliminate them 2 CONCLUSION 2 APPENDIX 1 2 Vector nature of angular momentum (the gyroscope effect) 2 BIBLIOGRAPHY 2 Books 2 Articles 2 Internet 2 Title: The flywheel as an alternative energy storage device for electric vehicles (EV): problems associated with the implementation, and possible solutions Abstract A recently flourishing technology, known as flywheel energy storage
The resistance of a wire.
Prediction I predict that if the length increases then the resistance will also increase in proportion to the length. I think this because the longer the wire the more atoms and so the more likely the electrons are going to collide with the atoms. So if the length is doubled the resistance should also double. This is because if the length is doubled the number of atoms will also double resulting in twice the number of collisions slowing the electrons down and increasing the resistance. My graph should show that the length is proportional to the resistance. The diagrams below show my prediction and should explain it more clearly: Conclusion In my prediction I said that : ¡§¡K.if the length increases than the resistance will also increase in proportion to the length.¡¨ From my graph I have shown that my prediction was correct, as the Line of Best Fit is a straight line proving that the resistance of the wire is proportional to the length of the wire. The length of the wire affects the resistance of the wire because the number of atoms in the wire increases or decreases as the length of the wire increases or decreases in proportion. The resistance of a wire depends on the number of collisions the electrons have with the atoms of the material , so if there is a larger number of atoms there will be a larger number of collisions which will increase the
Investigation into Friction.
INVESTIGATION INTO FRICTION Aim Our aim is to investigate the relationship between the frictional force between two surfaces, and the force needed to make the surfaces slide over one another. The investigation will also be into the type of surface and the amount of frictional force, and the force needed to make the surfaces slide. We will also be investigating the coefficients of friction on different surfaces. Theory Friction is the name given to the force, which opposes the relative sliding motion of two surfaces in contact with one another, as Ordinary Level Physics1 by AF Abbott tells us. This means that when two objects slide over one another, or touch one another, there is a frictional force present that tries to stop any sliding movement. The attractive forces between the molecules on the two surfaces cause friction, the Ordinary Level Physics says. Fig 12 shows two surfaces, and the cause of friction between them. The surfaces are not totally smooth, and so the particles oppose the forward movement of the others, and are also attracted to each other, causing friction. Fig 1. The more force there is acting on the surfaces, the more friction there is. This means that if there were a force of 10 N acting on the top surface, the friction would be greater than if no force other than gravity were acting on the top surface. There is also less friction between two
Bouncing Ball Experiment
Aim: To find out what affects the height to which a ball bounces. Variables: Height from which the ball is dropped Mass of the ball Material ball is made from External factors, i.e. changing air density, temperature The surface onto which the ball falls Prediction - reasons for variable control: Variables that will be altered: The height the ball is dropped from will affect the height the ball bounces to due to the energy chain the ball goes through as it is dropped and bounces up again. The energy chain is as follows: Therefore as energy cannot be created or destroyed the energy the ball starts with must be directly proportional to the energy the ball finishes with, at the top of its bounce, and so if the ball starts with more energy it must therefore finish with more. As in both cases the main form of energy is GPE it follows that the higher the ball is dropped from, the higher the ball will bounce. * The ball starts with more GPE * As there is more GPE more energy is converted into KE (The ball is going faster, KE=1/2mv2, v is greater therefore KE is greater by a larger amount). More thermal energy is also produced. * As there is more KE, more energy is converted into elastic potential energy * As there is more elastic potential energy, more energy is converted back into KE energy * As there is more KE energy, more work would need to act upon the ball in
In this Coursework, we were given the task of investigating some factors which affect the period of a simple pendulum.
PLAN INTRODUCTION: A pendulum is a device which consists of an object suspended from a fixed point that swings back and forth under the influence of gravity. This effect is known as gravitation. However simple it may seem, this structure is very beneficial in our everyday life for it is used in several kinds of mechanical devices such as the all popular grandfather clocks. In addition to this, a pendulum could determine the local acceleration of gravity. This is the case, as the strength of gravity varies at different latitudes and as gravity is one of the main forces acting on the pendulum, the acceleration of gravity could be noted. Further uses of the pendulum are found in the field of astronomy for some have been used to record the irregular rotation of the earth as well as to detect earthquakes and others are used to demonstrate the rotation of the earth. The pendulum and its applications were first discovered by Italian physicist and astronomer Galileo, who established that the period for the back-and-forth oscillation of a pendulum of a given length remains the same, no matter how large its arc, or amplitude. (If the amplitude is too large, however, the period of the pendulum is dependent on the amplitude.) This phenomenon is called isochronism. A pendulum can be seen as a device whose energy is continually changing. When the pendulum swings to & fro, its energy
Draw stress and strain graphs for the metal copper and the alloy constantan. Calculate the figures of young's modulus for copper and constantan. Discuss the physics involved.
AS Physics Data Analysis coursework This coursework assignment requires me analyse and evaluate data on copper and constantan given to me. It entails investigating the young's modulus of the metal and alloy. Thus I will use many methods during to complete my investigation. Aims: . To draw stress and strain graphs for the metal copper and the alloy constantan 2. To calculate the figures of young's modulus for copper and constantan 3. To discuss the physics involved Plan: In this investigation I have received results for extension of copper and constantan for certain forces applied to it, for which I will analyse and calculate the young's modulus. The results I have been given are forces applied to copper and constantan, three sets of results for the metal and alloy and this can be used by averaging data to give more accurate results thus these results given to me will be used to create graphs, calculate young's modulus and analyse data for both metals so I can complete my investigation. I will need to draw a force and extension graph for both copper and constantan, the extension shown will be the averaged value for each metal. I will also calculate the stress and strain values and plot this on a graph for both copper and constantan, I will plot these on the same graph and analyse the graph, hence I can find any patterns from the data and this will require me to draw
