Resistance Of A Wire

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Resistance of a wire Resistance Resistance can be defined as a force which opposes the flow of an electric current (electrons) around circuit. So energy is required to push the electrons around the circuit. The circuit can also resist the flow of electrons if the length of the wire used is long or the cross sectional area is large. The unit of resistance is measured in VA-1 or Ohms (Ω) and the formulae of resistance can be represented as this: RESISTANCE= VOLTAGE CURRENT Strategy What I am tying to find out is whether the thickness of a wire will affect the resistance of the wire. What I am going to measure in this experiment is the thickness of the wire and the resistance it gives. I am going to do this by measuring the thickness of the wire using a micrometer. The variables which will affect the resistance are: 1. Length: as the length of wire increases the electrons across it will have to travel a longer distance and in that process the electrons will take a longer time to move across the wire. Hence an increase in the length of wire will make the resistance increase. 2. Temperature: if the temperature in the wire is increased the atoms in the wire will vibrate more therefore causing more collisions, which makes the atoms pass in the way of the electrons. With this there would be an increase in resistance. 3. Material: The type of material used would affect the movement of electrons that are allowed to flow through the wire .If the atoms in the material are jammed together ,then their would be more collisions therefore increasing the amount of resistance. 4. Cross-sectional area: As the cross sectional area increases, electrons across the wire has more space to move about and less collisions resulting in less resistance .Therefore as the cross sectional area of a wire increases, the
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