The diagram at the shows 2 wires, the top one is only half the length of the bottom wire, there should be half the number of collisions between the electrons and the atoms but the wire under it is twice the length so it should be twice the number of atoms resulting in the twice as many collisions and the predicted doubling og the resistance.
Apparatus -
For me to be able to test the effect of the length on the resistance of a wire successfully, I will need to use the following:
- Cell or a power supplier (which will be the source of my voltage.
- Constantan wire (SWG 24) (which will be my the wire I will use to carry out my test).
- Ruler: measuring 100cm (which I will use to measure the length of my wire ).
- Bulb (which I will us to find my results ).
- Wires with crocodile clips (which I will use to connect the circuit with).
By Ali Hashem. Year 10 Boys.
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Diagram-
Method - At first I got all my apparatus together and set them the same way the diagram shows above. i used 1 bulb, a power supplier, 1 ruler (100 cm), 3 wires with crocodile clips, and a conducting wire (a constantan wire.)
As I have gathered all the apparatus in a circuit. I will use the bulb to measure the brightness of the bulb to see the resistance of the constantan wire from 10cm-50cm. I will then switch on the power supplier and set it to a voltage measuring 3V (so that the bulb doesn’t over heat or be too dime ). Then I obtain down the readings off each 10 cm so 10cm, 20cm, 30cm, 40cm and 50cm to see the resistance (V/I) of the conducting wire (constantan wire). The equation for this is =V/I.
Results -
By Ali Hashem. Year 10 Boys.
- Page 2 -
Conclusion -
In my coursework I decided to use a constantan wire as it has a high resistance unlike copper which has a low resistance and you we will not get accurate results for copper unlike constantan and I realise that the longer the length the more the resistance just as I expected the reason why is because of the electrons inside the wire. And I also conclude that my prediction is correct and that the longer the wire the greater the resistance due to the greater amount of collisions occurring inside the wire as the current travels through a further distance.
By Ali Hashem. Year 10 Boys.
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