How The Length Of A Wire Is Affected By The Resistance
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Introduction To investigate how the length of a wire affects resistance in an electric circuit, different lengths of wire will be placed in an electrical circuit and the effects will be observed. An ammeter and voltmeter will be used to measure the current and voltage in the circuit. Then, resistance will be worked out by dividing the voltage by current. Resistance is the measure of how hard it is for electricity to push through a circuit. All conductors resist the flow of current to some extent. Howeaver, some resist more than others. The...
Overall, the experiment went well as the data fully supported the prediction, with the exception of one outlier (the average of the 50cm wire test). The prediction was based on the theory that the longer the wire, the further the current has to travel which gives a longer amount of time that the current is travelling against the ions creating resistance (as explained in further detail previously in the Introduction). The fact that the data supported the prediction shows that the experiment was carried out well with at least an adequate amount of accuracy as it produced the results expected.

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Physics Investigation Of Resistance Aim:...Physics Investigation Of Resistance Aim: to investigate how the electrical resistance of a wire changes in relationship to it´s length. Prediction: I think that as the length of the wire increases so to will the resistance of it. I also believe that the rate at which the resistance of the wire increases will be directly proportional to the length. The graph to show this should therefore look something like this: Reason: with electricity, the property that transforms electrical energy into heat energy, in opposing electrical current, is resistance. A property of the atoms of all conductors is that they have free electrons in the outer shell of their structure. All metals are conductors and have an arrangement in similar form to this: As a result of the structure of all conductive atoms, the outer electrons are able to move about freely even in a solid. When there is a potential difference across a conductive material all of the free electrons arrange themselves in lines moving in the same direction. This forms an electrical current. Resistance is encountered when the charged particles that make up the current collide with other fixed particles in the material. As the resistance of a material increases so to must the force required to drive the same amount of current. In fact resistance, in ohmsR is equal to the electromotive force or potential difference, in volts V divided by the current, in amperes I "“ Ohm´s law. As the length of the wire is increased the number of collisions the current carrying charged particles make with fixed particles also increases and therefore the value for the resistance of the wire becomes higher. Resistance, in ohms R is also equal to the resistivity of the wire, in ohm-meters ñ multiplied by the length, in meters l divided by the cross sectional area, in square meters A. The material and cross sectional area of the wire is constant throughout the experiment. Therefore it is clear from the formula that the resistance should be directly proportional to the lengthKey factors: in this experiment we will only change one factor, the length of the wire. This should effect the resistance of the wire in the ways stated above. Fair test: in this experiment we are only changing one factor "“ the length of the wire, the factors that we are going to keep the same are as follows: We must keep the surrounding room temperature the same or the particles in the wire will move faster if the temperature is increased and this will therefore have an effect on the resistance. The cross sectional area of the wire must be kept constant throughout as well. This is shown in equation 2 where the cross sectional area is a factor that effects the resistance. The material of the wire must also be kept the same as different materials have different conductivity. The last two factors will be kept the same by using the same wire all of the way through the experiment. The current that we pass through the wire is to be kept the same, also. If this is changed the temperature of the wire might change in a way that is not constant making the results more confusing. Apparatus: 1. Wire, over 50 cm long 2. Rheostat 3. Power supply 4. Six connecting wires 5. Two crocodile clips 6. Voltmeter 7. Ammeter Plan: 1. Connect circuit as shown in the diagram. 2. Adjust rheostat until the ammeter reads .3 A. 3. Record voltage on voltmeter 4. Repeat the experiment with the following lengths of wire, connected between the two crocodile clips: - 10 cm - 15 cm - 20 cm - 25 cm - 30 cm - 35 cm - 40 cm - 45 cm - 50 cm 5. Use Ohm´s law to find the resistance of the wire, equation 1. Diagram: Safety: this is not a very dangerous experiment but despite this you must always handle electricity with care, keep the current low, handle with dry hands etc. Accuracy: to keep this experiment as accurate as possible we need to make sure, firstly, that the length of the wire is measured precisely from the inside edge of the crocodile clips, making sure that the wire is straight when we do this. We must also make sure that the wire is straight when we conduct the experiment. If it is not, short circuits may occur and bends and kinks in the wire may effect the resistance, also. The reading that we take of the voltage should be done fairly promptly after the circuit is connected. This is because as soon as a current is put through the wire it will get hotter and we want to test it when heat is effecting it the least, i.e. at the beginning Preliminary: upon testing to see if the experiment would work I found no problems with the plan I described earlier. I was able to get the following results: LENGTH cm CURRENT A VOLTAGE V RESISTANCE =V/IÙ 10 0.3 0.13 0.43 15 0.3 0.20 0.66 20 0.3 0.27 0.90 25 0.3 0.35 1.16 30 0.3 0.42 1.40 35 0.3 0.48 1.60 40 0.3 0.57 1.90 45 0.3 0.60 2.00 50 0.3 0.68 2.26 Observations Observations: we will observe the reading on the voltmeter change as we change the current to .3 A. we also observe a general increase in the voltage as the length of wire we use gets longer. The rheostat will also be set at different positions for the different lengths of wire that we use. Evidence: to make sure our overall values are as accurate as possible we will repeat our readings 3 times and then take the mean resistance of the 3 readings. We will also be able to spot and discard any anomalies from our results. Results: Set i Length cm Current A Voltage V Resistance =V/I in Ù 10 0.3 0.13 0.43 15 0.3 0.20 0.66 20 0.3 0.27 0.90 25 0.3 0.35 1.16 30 0.3 0.41 1.36 35 0.3 0.48 1.60 40 0.3 0.56 1.86 45 0.3 0.62 2.06 50 0.3 0.69 2.30 Set ii Length cm Current A Voltage V Resistance =V/I in Ù 10 0.3 0.13 0.43 15 0.3 0.20 0.66 20 0.3 0.27 0.90 25 0.3 0.35 1.16 30 0.3 0.42 1.40 35 0.3 0.49 1.63 40 0.3 0.57 1.90 45 0.3 0.61 2.03 50 0.3 0.70 2.33 Set iii Length cm Current A Voltage V Resistance =V/I in Ù 10 0.3 0.13 0.43 15 0.3 0.20 0.66 20 0.3 0.28 0.93 25 0.3 0.34 1.13 30 0.3 0.40 1.33 35 0.3 0.48 1.60 40 0.3 0.57 1.90 45 0.3 0.62 2.06 50 0.3 0.70 2.33 Average Length cm Resistance Ù-Set i Resistance Ù-Set ii Resistance Ù-Set iii Mean Resistance Ù 10 0.43 0.43 0.43 0.43 15 0.66 0.66 0.66 0.66 20 0.90 0.90 0.93 0.91 25 1.16 1.16 1.13 1.15 30 1.36 1.40 1.33 1.38 35 1.60 1.63 1.60 1.61 from 40 1.86 1.90 1.90 1.89 45 2.06 2.03 2.06 2.05 50 2.30 2.33 2.33 2.32 Anomalies: there was only one real anomaly in this experiment and it has been highlighted like this: 000 Analysis Trends: from the graph we can see one very clear trend, which is, as the length of the wire increases so does the resistance of it. Another, more significant thing is that it the increase is constant. This is indicating by the fact that the line drawn is a straight one. One may also note that the gradient of the line drawn is 1.85/40 .04625. Conclusion: I think that from my results I can safely say that my prediction was right. The resistance did change in proportion to the length. This is because as the length of the wire increased the electrons that made up the current, had to travel through more of the fixed particles in the wire causing more collisions and therefore a higher resistance. We can work out what the resistivity of the wire should be from our results using the It is obvious from the formula that R/l is simply the gradient of the graph, therefore Evaluation I feel that overall our results were quite accurate. This is can be seen when we look at the graph, which shows a straight line with all of the points apart from one being very close to or on that line. The one point that was not that close to the line was a slight anomaly, but it was only slight and did not effect the final gradient of the graph. I have found out that for the wire I was using, the resistivity at 20©C is 4.9 X 10-7 ohm-meter. From this we can then work out the percentage error of our results: The accuracy for this experiment is, theoretically, ± 15.7%, but as one can see this does not seem to be the case from looking at the graph. The reason for this could have been due to a number of different factors. Firstly the temperature of the wire was not necessarily 20©C when we conducted the experiment and the material of wire may not be as pure as it should have been. The main reason for this was probably due to the equipment that we used being inaccurate. This did not stop us from seeing the trend, though, because the equipment would have been out by a constant amount each time therefore there was a constant error. So the trends that were predicted in the plan still were shown. Most errors in our experiment were encountered in the measuring of the wire. This is because it simply was not very practical to hold a piece of wire straight, whilst holding it next to a ruler and then trying to accurately fix crocodile clips to the right part on the wire. Also I do not feel that the crocodile clips were always fixed securely to the wire with a good connection. This also meant that they were easy to move about on the wire changing the length of it. Errors rarely occurred in the setting of the current and the reading of the voltage. It was just in the preparation area that they did occur. Another example of this is the wire was never totally straight when we started the experiment, which may also, as said earlier on, effect the resistance of it I do not think that doing any more results in our experiment would have made it any more accurate. I feel that the only way to make it more accurate would be to use a different method "“ perhaps were we had a bar that did not bend in place of the wire. We could even use a rheostat in place of the wire, because it is essentially a long coiled wire that is connected at different lengths to change the resistance of the circuit   

Physics Investigation Of Resistance Aim: to investigate how the electrical resistance of a wire changes in relationship to it´s length. Prediction: I think that as the length of the wire increases so to will the resistance of it. I also believe that the rate at which the resistance...

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For many centuries, scientists have been...For many centuries, scientists have been puzzling over the question "What is everything made of?". There have been numerous theories and hypotheses drawn up over the millennia, but only one can be correct. This is atomic theory "“ that everything is composed of atoms, which is the smallest any one element can be and cannot be broken up any smaller. Of course, no one person has ever just clicked his or her fingers and exclaimed Archimedes-fashion "Eureka!" and settled the score forever, but the theory today has been based upon the work of many great scientists over time. In this essay I shall look at just a drop in the ocean as far as these are concerned, on the subject of changing atomic models. John Dalton 1766-1844 developed the first useful atomic theory of matter around 1803, developing a hypothesis that the sizes of the particles making up different gases must be different. He came up with the four following points: "¢ All matter consists of tiny particles "¢ Atoms are indestructible and unchangeable - atoms of an element cannot be created, destroyed, broken into smaller parts or transformed into atoms of another element. Dalton based this hypothesis on the law of conservation of mass and on centuries of experimental evidence. "¢ Elements are characterized by the mass of their atoms. All atoms of the same element have identical weights, Dalton asserted. Atoms of different elements have different weights. With the discovery of isotopes, however, the statement was amended to read, "Elements are characterized by their atomic number". "¢ When elements react, their atoms combine in simple, whole number ratios. This suggested a practical strategy for determining relative atomic weights from elemental percentages in compounds. Experimental atomic weights could then be used to explain the fixed mass percentages of elements in all compounds of those elements! Some of the details of Dalton"s original atomic theory are now known to be incorrect. But the core concepts of the theory that chemical reactions can be explained by the union and separation of atoms, and that these atoms have characteristic properties are foundations of modern physical science. One classic diffraction experiment, which examined diffraction of alpha particles helium nuclei containing two positive charges by a thin foil made of gold metal, was conducted in 1911 by Hans Geiger and Ernest Marsden at the suggestion of Ernest Rutherford. Geiger and Marsden expected to find that most of the alpha particles travel straight through the foil with little deviation, with the remainder being deviated by a percent or two. This thinking was based on the theory that positive and negative charges were spread evenly within the atom and that only weak electric forces would be exerted on the alpha particles that were passing through the thin foil at high energy. What they found, to great surprise, was that while most of the alpha particles passed straight through the foil, a small percentage of them were deflected at very large angles and some were even backscattered. Because alpha particles have about 8000 times the mass of an electron and impacted the foil at very high velocities, it was clear that very strong forces were necessary to deflect and backscatter these particles. Rutherford explained this phenomenon with a revitalized model of the atom in which most of the mass was concentrated into a compact nucleus holding all of the positive charge, with electrons occupying the bulk of the atom"s space and orbiting the nucleus at a distance. With the atom being composed largely of empty space, it was then very easy to construct a scenario where most of the alpha particles passed through the foil, and only the ones that encountered a direct collision with a gold nucleus were deflected or scattered backwards. Of course, these are just two of the many findings in this field of scientific research, but what they have helped prove is the basis on all elements and their atoms "“ only now can scientists predict and understand reactions to such a level of accuracy.   

For many centuries, scientists have been puzzling over the question "What is everything made of?". There have been numerous theories and hypotheses drawn up over the millennia, but only one can be correct. This is atomic theory – that everything is composed of atoms, which is the smallest any one...

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Aim: To investigate the heat... Aim: To investigate the heat loss of the insulating materials, bubble wrap, cotton wool, blanket and foil Introduction: I will carry out this investigation by measuring the temperature of hot water in beakers insulated with these materials. Naturally the insulated beaker with the warmest water will have prevented the most heat loss. To understand how materials prevent heat loss I need to look at the three ways in which heat can be transferred or lost to the surroundings. One of the ways is conduction. This is when heat energy is transported along an object from the hotter region to the cooler region. The object itself does not move. So when an object is heated, its atoms start vibrating with the heat energy. The free electrons begin to diffuse through the object and collide into other electrons transferring kinetic energy. Substances that have particles close together, like metals are good conductors. Meanwhile gases have particles that further apart so they are poor conductors. Therefore things that are made of particles that are not close together, are poor conductors but good insulators such as gases. Another way is convection, which only happens in liquids and gases. This is when heated particles start moving faster so they move further apart. The heat also makes the particle expand so they become less dense than the unheated particles. As a result of this, the heated particles rise upwards taking the extra energy with them and are replaced by colder and denser regions. A form of convection is in evaporation where the particles in a liquid keep bumping into each other. Sometimes they collide with each other with kinetic energy. During these collisions some particles receive so much energy that they can break away from the liquid. The final way in which heat can be lost is through radiation. This is the transfer of heat energy by waves. Every object sends out infra red radiation but hotter objects send out more. This is completely different to conduction and convection as it does not require particles, so the so infra-red radiation can pass through a vacuum. Also dull and black surfaces emit more heat while shiny and white surfaces emit less. However this makes black and dull surfaces better absorbers Prediction: With the kinetic theory on mind, I predict that out of the materials of foil, bubble wrap, wool and blanket the bubble wrap will be the better insulator. This is because the bubble wrap has a lot of air trapped in its pockets. Air is a very good insulator as its particles are widely spread out therefore there is a less chance of them colliding and passing energy on. This means that there will be less energy transferred to the surroundings, as the bubble wrap would prevent heat loss mainly through conduction. Furthermore the material is made from plastic which in itself is a good insulator. As the aluminium foil is shiny it will reduce heats loss through radiation by reflecting heat back in, like a flask. However since it is a metal, some heat will be lost through conduction. Naturally the blanket material would be a good insulator as its purpose is to keep people warm. This because it has lots of layers and like the wool has air trapped between it fibres. So by reducing heat loss through conduction it should be a good insulator but not as good as the bubble wrap. This is because as it is a dull and black colour some heat will be lost through radiation. The cotton wool is also material that has a lot of trapped air in between its many fibres. Even though it is a good insulator, I feel that because of the thinness of the material the bubble wrap will still be the better insulator. All these materials except the foil are lagging which are insulating materials that have tiny air pockets that trap air to prevent heat from being conducted away. Safety: Since I am dealing with very hot water there are precautions I will need to take. Firstly I will abide to the general laboratory rules i.e. tidy workspace, loose clothing tucked away, and safety goggles. When I need the water for my experiment I will my teacher to pour the hot water. Preliminary investigation: For my investigation I need to know at what intervals I should record a temperature reading and for what period of time. Here are the results of my preliminary investigation: Time Secs Temperature °C 0 84.5 30 80.5 60 77.0 90 75.5 Time Mins Temperature °C 0 84 1 80 2 74 3 72 These results show that taking the temperature readings at 30 second intervals would make the results more accurate and to do this over a 5 minute period. I will also use 80 ml of boiling water and make sure all starting temperatures are the same. Range of results: My results will fit into a table like this, TIME SECS TEMPERATURE OF WATER IN BEAKER ºC CONTROL WOOL BUBBLE FOIL BLANKET Apparatus: In my experiment I will use the following equipments: Electric Kettle "“ To boil the water 5 Beakers "“ To hold the hot water for the experiments Aluminium Foil Bubble Wrap Cotton Wool Blanket Thermometer "“ To measure the temperature Stopwatch "“ To time the experiments Elastic Bands "“ To hold the materials in place Variables: In my experiment the volume of the water for each beaker will be 80 ml. Temperature readings will be taken at 30 second intervals for 5 minutes and I will make sure all beakers have the same starting temperature. Therefore there will 10 readings after the starting temperature. This will ensure my test is fair. The only thing that will be different is the material around the beakers. Method: First of all I will wrap four of the beakers in the materials with the elastic bands. The other beaker will stay uncovered as it is the controlled experiment. After placing the thermometer into the beaker, the 80 ml of water will be poured in and the stopwatch will be started straight away. Also the starting temperature recorded. After that the temperature reading will be recorded at 30 second intervals shown by the stopwatch. This will be done for 5 minutes and repeated for all the beakers. Results: TIME SECS TEMPERATURE OF WATER IN BEAKER ºC CONTROL WOOL BUBBLE FOIL BLANKET 0 83.0 83.5 83.0 83.5 83.5 30 80.5 80.0 81.5 79.5 80.5 60 77.0 78.0 80.0 77.5 78.5 90 75.0 76.0 78.5 76.0 76.5 120 73.5 74.5 76.5 74.0 75.5 150 72.0 73.5 75.5 73.5 74.5 180 70.0 72.5 74.5 72.5 73.5 210 69.0 71.5 74.0 71.5 72.5 240 68.0 70.5 73.0 70.5 71.5 270 66.5 70.0 72.5 69.5 71.0 300 65.5 69.5 72.0 68.5 70.5 Observations: For all the materials there is a sharp drop in temperature for the first minute and after that it gradually slows down. The starting temperatures for the insulated beakers are very close but at 5 minutes they the end readings are more spread out. As you can see on the graph the bubble wrap has the most gradual curve and consequently the slowest rate of heat loss. From the starting temperature of 83.0 °C, it dropped by 12.0 °C after 5 minutes. The blanket is the second best insulator with the temperature drop of 13 °C from a starting temperature of 83.5 °C. The cotton wool lost 14.0 °C from a starting temperature of 83.5°C The aluminium foil is the worst insulator from the materials as from a starting temperature of 83.5 °C it lost 15 °C The controlled experiment the beaker with no insulation has the steepest curve and therefore the fastest heat loss. From the starting temperature of 83.0 °C, it lost 17.5 °C after 5 minutes. Conclusion My prediction was correct as the bubble wrap material was the best insulator because it prevented the most heat loss being the best insulator. The bubble wrap was the best insulator due to its ability to reduce heat loss through conduction. This can be understood by looking behind theory of conduction. Since heat is energy associated with the motions of the particles making up a substance, it is transferred by these motions, shifting from regions of temperature, where particles are more energetic to regions of lower temperature. The rate of heat flow between the two regions is relative to the temperature difference and the heat conductivity of the substance. In solids the molecules are bound and add to the conduction of heat mainly by vibrating against neighboring molecules. However a more important mechanism is the migration of free electrons. Materials such as metals have a high free-electron density therefore they are good conductors of heat while non-metals do not conduct as well. Since gases and liquids have their molecules even further apart they are generally, very poor conductors which makes them good insulators. Therefore the bubble wrap which is made up of lots of air pockets has not only less free electrons to transfer heat but it has molecules the trapped air that are quite far apart. This makes harder for heat from the boiling water in the beaker to be conducted away through the bubble wrap and to the surroundings The blanket and cotton wool were also quite good insulators as they too have a lot of air trapped between the fibres. The foil was not as good because being a metal it had more free electrons with particles being closer together, for heat to be conducted away to other regions. However, since it was quite shiny it reflected some heat back in, to the beakers, such as the effect of a flask so it prevented heat loss better than the controlled beaker. The controlled beaker naturally let out the most heat since it had no form of insulation except the fact that it the beaker was made out of glass which in itself is a fairly good insulator. Evaluation The method that I used to carry out my investigation was fairy simple to carry out. It required me to pour out 80 mls of hot water into beakers insulated with different materials. The temperature of the water was then recorded over a 5 minute period at 30 second intervals. The results of my investigation were accurate as I took my readings at eye-level to the nearest half a degree centigrade. I had no anomalous results and the accuracy can be seen on my results graph where the readings are close to the best fit curve. However I could have been even more accurate as if the time h d been available tome, I would have repeated my experiments to get an average of the results. Another way in which I could have improved my experiment was if was available to me, I would have used a data logger with temperature probe. This would have given me very accurate readings every second. I could have also used polystyrene lids to reduce heat loss by convection in the beakers. To extend by investigation I could have used different beakers like copper cans to see how the material of the beaker affects the rate of heat loss. In addition I could look at the effect of the amount of layers of material insulating the beaker as well as looking at different volumes of boiling water.   

Aim: To investigate the heat loss of the insulating materials, bubble wrap, cotton wool, blanket and foil Introduction: I will carry out this investigation by measuring the temperature of hot water in beakers insulated with these materials. Naturally the insulated beaker with the warmest water will have prevented...

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Aim:- We will investigate... Aim:- We will investigate the length of a wire in a series circuit, and if it will affect its resistance. Prediction:- Resistance is the force of which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around the circuit. I predict the resistance will vary with the length. I also predict the longer the wire the less current will flow which increases the resistance. This is because electric current is the movement of electrons through a conductor, so when resistance is high, conductivity is low. Therefore, the electrons will have to push their way through a shorter path of atoms in the wire, reducing their resistance. Whereas, if the length was longer, then the number of atoms in the wire increase. Electrons are negatively charged particles, and protons are positively charged atoms. Electrons move around, but protons don't move, they stay in the same place. Current is a flow of electrons, and is measured in amperes A. When a current flows through a resistance, energy is given off as heat. I think the thicker and shorter the wire, the lower the resistance. I think this because, for example, if you had a road with cars parked to the side and only one car at a time can pass the cars parked on the side of the road as the road is so narrow that allows two cars to go at a time, but as it seems that there are cars parked, that only one car can move past the parked cars; in this case it will be slower for the cars to pass, because the road is long and narrow. Whereas, if the road was wider thinker and shorter it would be quicker. DIAGRAM OF THE THICKNESS AND LENGTH Planning:- Before I do start my investigation I will need to set up my circuit. I will need a variable resistor connected to a power supply, an ammeter and a voltmeter voltmeter parallel to the nichrome wire. I will move the knob on the variable resistor into five different positions for each one length e.g:- 10cm, 20cm, 30cm "¦"¦.. I will get five different readings for each length, and I will be doing five different lengths, which makes twenty-five readings all together, on the voltmeter and ammeter. I will calculate the resistance with this equation:- V = R x I OR Potential difference volts, V = Current amps, A x Resistanceohm, This is how my circuit will look like when I've finished setting it up:- DIAGRAM OF CIRCUIT I will link all the components together with the wire connected to the circuit with crocodile clips at the length of 10cm. I will use to measure the voltage using a voltmeter and recording the results on a table. I will also need to measure the current using an ammeter and recording the results for them too. When I have the results I require, I will use the calculator and divide the voltage by the current to get the resistance. I know that I will need to turn off and on the power supply every time I investigate another length of the wire. This is because the wire intends to warm up and this may have an effect on my other readings and also the wire can snap in half by melting. To keep my investigation fair, I will keep the voltage on the power supply the same, the type of wire and the thickness, and also do the investigation in the same surrounding temperature. Analysing:- I have calculated the resistance of each length on the nichrome wire. I have used these results of values to plot a graph of resistance against length. Length goes along the bottom axis because it is the dependent variable. Its value depends on the length of the wire chosen The points on my graph are a little scattered, none of the points touch the line of best fit, but they are quite close together.. On my graph of the length against gradient, I have rejected one point. I would of rejected two, but I have noticed that the 10cm point was very high, I was going to also reject the 40cm point too, but I was more curious on the 10cm. my table of results suggests that the voltage reading for one point in the 10cm trial was very high compared to the other results of 20cm, 30cm, 40cm and 50cm. but I reckon that I must of miss read the meters whilst investigating. I have noted my working out on the graph of current against voltage. On my graph of current against voltage, there is an anomalies point which I have circled. It is the 10cm point of 0.90V and 0.18A which I must have rejected on the graph of length against gradient. So this is the reason of my rejection on the graph of length against gradient. You can see that this one point has affected the gradient. And as I mentioned that I must of miss read the meters.   

Aim:- We will investigate the length of a wire in a series circuit, and if it will affect its resistance. Prediction:- Resistance is the force of which opposes the flow of an electric current around a circuit so that energy is required to push the charged...

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Mankind has always been fascinated with...Mankind has always been fascinated with the thought of what everything is made of. The answer can be found in the periodic table but that hasn't always been the case"¦"¦"¦ Once upon a time in a kingdom far, far away live a Greek scientist called Aristotle shown right. Around 300BC he declared that every thing is made up of only four elements. These were fire, air, water and earth and that all matter is made up of four elements. Also that matter had four properties, hot, cold, dry and wet. But this did not satisfy ever one and so the next person to challenged this idea was the idea of Hennig Brand. Brand was the first person to discover a new element. He was a bankrupt German merchant who was trying to discover the Philosopher"s Stone which was supposed to turn inexpensive metals into gold. He experimented with distilling human urine until in 1669 he finally made a glowing white substance which he named phosphorus. He kept his discovery secret, until 1680 when Robert Boyle rediscovered it and it became public. Then later in 1789 Antoine-Laurent de Lavoisier shown here released his Traité Élémentaire de Chimie it was thought to be the first chemical text book. It contained a list of elements, or substances that could not be broken down further, which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc, and sulphur and a further 26 what he thought to be elements. While many leading chemists of the time refused to believe Lavoisier"s new revelations, the Elementary Treatise was written well enough to convince the younger generation. This model only classified elements into metals and non-metals and so was not accepted. The next knight in shining armour to continue the periodic table legassy was Jons Jakob Berzelius who introduce a table of atomic weights. In his weights, he used oxygen as a standard, setting its weight equal to exactly 100. He also measured the weights of 43 elements. This paved the way for the German chemist Johann Dobereiner right. In the 1820s Döbereiner noticed an interesting pattern in some sets of three similar elements. He noticed that the atomic mass lay roughly halfway between the lightest and heaviest ele ments in the group of three. He called this group the triads. Then many elements had not yet been discovered and some substances were thought of as elements that were actually compounds. So it"s not surprising that Döbereiner could only find a few triads. Certain triads were calcium, strontium & barium and chlorine, bromine & iodine. Then came along the British chemist John Newlands. In 1864 he suggested that if the elements are put in order of atomic mass, every eighth element was similar. He called this his Law of Octaves. This pattern only worked for the first 15 or so elements known at that time. Fellow scientists at the time were not very impressed. Some big bad wolves even said that he might have had better luck putting the elements in alphabetical order. It was a few years later that the real breakthrough came. A Russian chemist called Dmitri Mendeleev shown hard at work was also struggling to find any underlying pattern in the chemistry of the elements. This knight in shining armor also thought that the key was to arrange the elements in order of atomic mass. But try as he might he didn't know why the pattern kept breaking down. He spent about 13 years gathering data on the problem and eventually solved it by deciding to leave gaps so that similar elements could always line up in vertical columns. Mendeleev enjoyed playing card game patience so he made a card for each element. This helped him working out his solution as he made lines of similar elements, one on top of another. Eventually he published what he called his " Periodic Table'. At the time, many scientists doubted Mendeleev"s theory because he left gaps and changed the order of elements to make his table work properly. However, he won them over by predicting the properties of elements that were as yet undiscovered from the patterns evident in his table. When the element germanium was discovered in 1886, it closely matched the properties Mendeleev had predicted using his Periodic Table. The science community of that time was dumbstruck at that Russian scientist and his new table, and today people still think it an extremely groovy piece of science. Mendeleev's table stood strong until the beginning of the 20th Century. The discovery of atomic properties led to the quantum theory which was a clever piece of science only understood by three or four magic wizards on this planet. The periodic table of the elements was reorganized to accommodate this new theory, made to look like how we know it today. The original sorting organized by Mendeleev was dropped in favor of the more logical sorting according to the atomic number and the groups were arranged according to their electronic configuration. *Even now the periodic table of the elements as we know it is not complete and every now and again a knight steps forth and takes on the legacy of his fore fathers and a new element is synthesized and added to Periodic table. And so the Periodic table was used for ever more and that is why its founders will live happily ever after.   

Mankind has always been fascinated with the thought of what everything is made of. The answer can be found in the periodic table but that hasn't always been the case……… Once upon a time in a kingdom far, far away live a Greek scientist called Aristotle shown right. Around 300BC...

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