Length and Resistance of a Wire

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Length and Resistance of a Wire Brief How is resistance of a wire affected by the length of a wire. How will I do it? I will have to measure out lengths of bare wire, all of the same type of metal, thickness, and keep them at the same temperature (to keep the experiment reliable and precise) I will use constants of voltage and variables of lengths of wire. I will also measure the current and voltage by using a voltmeter and ammeter for extra reliability. I must take in to account that temperature is very important as it can lose energy in the particles and I will have to measure the resistance of the circuit without the bare wire. To measure the resistance of each length of wire by using the equation: R = V / I Where R = resistance V = Pd. Across the conductor I = current This formula will give me a result in Ohms (?) From the circuit s I have made previously in school, I used that knowledge to produce the most efficient circuit for the experiment. Apparatus Ammeter - 0-5 Amperes Voltmeter - 0-5 Volts Wires - insulated Bare wire - 1.6mm, and lengths of 10cm 20cm 30cm 40cm Power supply - Ac, 0-5 volts Circuit (your diagram) My circuit is set up like this to make accurate results, the ammeter is in series so all of the amps, have to travel through the ammeter. (it would reduce the number of amps if it was in a parallel circuit because some of the amps have to travel along the other wire). The voltmeter is in parallel with the wire because the volts are equal across the circuit when in parallel. Things that I will measure Volts - voltmeter Amps - Ammeter Temperature - close watch on wire (keep voltage low) Resistance - Formula (R=V/I) Prediction I think that the longer the wire, the more resistance, as preliminary

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