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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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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Planning: Aim The aim...Planning: Aim The aim of this experiment is to show how the height of a ramp from which a trolley rolls down will affect its run off speed. Preliminary The preliminary experiment we did prior to the investigation enabled me to choose what factors of the investigation I should keep the same or alter. My results from the preliminary displayed that I should perform the following procedures: - "žh The heights that allow the trolley to go down the ramp at a suitable velocity and whereabouts on the ramp I would allow the trolley to go from inorder to make the test fair and the speed accurate. I found out in the preliminary that 0.05m would be to low a height to begin with and that the trolley would not move fast enough therefore would not reach the end of the 1m run way causing a break in my results. Then also that if I suspended the ramp higher than 0.5m it was too high, and again I would not be able to gather any results as the trolley would be going to fast. "žh That the trolley would be positioned with its back wheels over the edge of the ramp each time we carried out the investigation, this was to ensure us that each time the trolley was started at the same place, making our results accurate; "žh I discovered how it would be possible and enable me to keep my ramp at an inclination without having to hold it the whole time. "žh I decided that I was going to have to put a file and wedge of paper at the end of the ramp to prevent the trolley jumping, and implementing it to go straight to the end of the ramp smoothly therefore not effecting my results. "žh In the preliminary I decided that I would keep the ramp at a certain height by using a clamp and that the range of heights that I would use would be 0.10m, 0.20m, 0.30m, 0.40m, 0.50m "žh I decided that I would leave a metre after the ramp for the trolley to run off, as this was an appropriate distance for me to collect my times. "žh I would also use a tickertape vibrator, as a high degree of accuracy is required in this experiment and any inaccurate readings in my results, I do not want to be due to human error. The accuracies of these 2 instruments are as follows: Stopwatch/clock 1/10 s Tickertape vibrator 1/50 s The table of results below is to show which method of timing proved to be most accurate: Height m Time using stopwatchs Time using tickertimer s 10 1.76 1.59 10 1.56 1.47 30 0.67 0.97 30 0.91 1.04 Prediction I predict that the higher the ramp is the faster the speed of the trolley will be and the average velocity and time will not be directly proportional. Due to gravitational potential energy GPE which is the amount of energy that an object has because it its position. The higher the object is the more GPE it has and my table below proves   

Planning: Aim The aim of this experiment is to show how the height of a ramp from which a trolley rolls down will affect its run off speed. Preliminary The preliminary experiment we did prior to the investigation enabled me to choose what factors of the...

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