Resistance in wires.

Resistance in wires. Aim: To alter the length of wire and measure the effect on the resistance.Apparatus: 3 wires of widths 28, 30 and 36.1 ammeter - to measure the current in amps4 crocodile clips - attach to the wires6 leads - use to connect circuitRuler - to measure length of wireMasking tape - measure and tape against the rulerPower pack - supply energy in voltsVolt meter - measure the voltage in voltsVariable resistor - control the resistanceBrief: First I will carry out a pre-test where I will test the 3 widths and then choose one that has the lowest resistance meaning it has a higher current. Once I have completed the pre-test, I will carry out the experiment. I will change the length of the wire about 5 times each at 5 different volts for the input. I measure the output voltage using a voltmeter and the current using an ammeter.Scrap Metal Recycling PilePower packVariable resistorAmmeterWireVoltmeterVariables to keep fair test:‚Â ·Length of wire - input‚Â ·Resistance - it will be kept t he same‚Â ·Voltage - will alter‚Â ·Current in amps - output‚Â ·Width of wire‚Â ·Temperature‚Â ·Type of metal for wireMetallic bonding theorye- e- e-+ + +Free electrons move e- e- a sea of electronsWhen pushed by volts + +e- = Delocalised electrons+ = Metal cationAs the metal cations and the electrons are oppositely charged, they will be attracted to each other, and also to other metal cations. These electrostatic forces are what hold the particles together in metals.Metallic bonding is present in all metallic elements. Positive ions of the metallic element form a giant lattice (regular arrangement), with the valency electrons floating over them. This means that the electrons...