Wire Coursework
GCSE Physics Coursework - Resistance of a Wire Coursework
Introduction (Theory)
In this piece of Coursework I am going to investigate the resistance in a piece of wire. Resistance is the force that slows down the flow of electrons; this can be due to electrons colliding. The total length of the wires will affect the amount of resistance. The longer the wire, the more resistance that there will be. This is also true for thickness of wire; the thinner the wire is the more resistance. Resistance is measured in ohms, the symbol is Ω. The equation for measuring resistance (Ω) is Voltage (V)/Current (I) =Resistance (Ω)
Aim
In this Investigation I am going to investigate how the length of a wire affects resistance. …show more content…
Variables
For this investigation I will vary the length of wire to see the resistance at each length. For the controlled variables I will keep, current in circuit, width of wire, material of wire and temperature of wire the same.
Prediction
I predict there will be more resistance the longer the wire is. This is because the electrons will have more chance to collide in a longer wire, than they do in a short wire. If I had a 100 cm wire it would be double the resistance of a 50 cm wire
Method
50cm length wire is fixed to a half a metre rule. The power supply is turned on. The voltage and flow are then read off the ammeter and voltmeter, and recorded, then do the same for 5cm intervals.
Diagram
List of equipment
A voltmeter, an ammeter, a crocodile clip, a power supply, 26 nicrome wire, ruler
Safety
In order to perform a safe experiment, we will keep the voltage low (3v) so the chance of overheating is low.
Also i will turn off the power supply before changing the length of the wire
Results
5 Volts wire nickel Chrome swg
Length amps Volts ResistanceΩ
50cm 0.46 1.77 3.85Ω
45cm 0.46 1.62 3.52Ω
40cm 0.46 1.43 3.11Ω
35cm 0.46 1.29 2.80Ω
30cm 0.46 1.21 2.63Ω
25cm 0.46 0.90 1.96Ω
20cm 0.46 0.80 1.74Ω
15cm 0.46 0.70 1.52Ω
10cm 0.46 0.40 0.87Ω
5cm 0.46 0.22 0.47Ω
Length amps volts ResistanceΩ
50cm 0.46 1.82 3.96 Ω
45cm 0.46 1.59 3.46 Ω
40cm 0.46 1.33 2.89 Ω
35cm 0.46 1.28 2.78 Ω
30cm 0.46 1.2 2.61 Ω
25cm 0.46 0.91 1.98 Ω
20cm 0.46 0.75 1.63 Ω
15cm 0.46 0.61 1.33 Ω
10cm 0.46 0.45 0.98 Ω
5cm 0.46 0.24 0.52 Ω
r average volts average resistance
1.61 3.5
1.29 2.80
0.95 2.07
0.83 1.80
0.73 1.59
0.41 0.89
0.3 0.65
0.21 0.46
0.09 0.2
0.03 0.07
Conclusion Having performed the investigation, the following conclusions are: As predicted, the longer in length the bigger the resistance for example at 5cm the resistance is 0.52 Ω and 50cm the resistance was 3.96 Ω. This can be clearly said for the 1st,2nd and average
results
The electrons didn't collide as much in the shorter wire because there was less time to do so, this leads to less resistance.
The wire show a strong trend of a straight line, i.e. the length of the wire is shown to be nearly proportional to the resistance double the length and the resistance doubles.
The overall resistance of the three results don't differ considerably.
Evaluation
In my Investigation I could of done more tests too make. My results more consistent. My Method could have been better, the wire was lose in some places making the results not as accurate.
Introduction (Theory)
In this piece of Coursework I am going to investigate the resistance in a piece of wire. Resistance is the force that slows down the flow of electrons; this can be due to electrons colliding. The total length of the wires will affect the amount of resistance. The longer the wire, the more resistance that there will be. This is also true for thickness of wire; the thinner the wire is the more resistance. Resistance is measured in ohms, the symbol is Ω. The equation for measuring resistance (Ω) is Voltage (V)/Current (I) =Resistance (Ω)
Aim
In this Investigation I am going to investigate how the length of a wire affects resistance. …show more content…
Variables
For this investigation I will vary the length of wire to see the resistance at each length. For the controlled variables I will keep, current in circuit, width of wire, material of wire and temperature of wire the same.
Prediction
I predict there will be more resistance the longer the wire is. This is because the electrons will have more chance to collide in a longer wire, than they do in a short wire. If I had a 100 cm wire it would be double the resistance of a 50 cm wire
Method
50cm length wire is fixed to a half a metre rule. The power supply is turned on. The voltage and flow are then read off the ammeter and voltmeter, and recorded, then do the same for 5cm intervals.
Diagram
List of equipment
A voltmeter, an ammeter, a crocodile clip, a power supply, 26 nicrome wire, ruler
Safety
In order to perform a safe experiment, we will keep the voltage low (3v) so the chance of overheating is low.
Also i will turn off the power supply before changing the length of the wire
Results
5 Volts wire nickel Chrome swg
Length amps Volts ResistanceΩ
50cm 0.46 1.77 3.85Ω
45cm 0.46 1.62 3.52Ω
40cm 0.46 1.43 3.11Ω
35cm 0.46 1.29 2.80Ω
30cm 0.46 1.21 2.63Ω
25cm 0.46 0.90 1.96Ω
20cm 0.46 0.80 1.74Ω
15cm 0.46 0.70 1.52Ω
10cm 0.46 0.40 0.87Ω
5cm 0.46 0.22 0.47Ω
Length amps volts ResistanceΩ
50cm 0.46 1.82 3.96 Ω
45cm 0.46 1.59 3.46 Ω
40cm 0.46 1.33 2.89 Ω
35cm 0.46 1.28 2.78 Ω
30cm 0.46 1.2 2.61 Ω
25cm 0.46 0.91 1.98 Ω
20cm 0.46 0.75 1.63 Ω
15cm 0.46 0.61 1.33 Ω
10cm 0.46 0.45 0.98 Ω
5cm 0.46 0.24 0.52 Ω
r average volts average resistance
1.61 3.5
1.29 2.80
0.95 2.07
0.83 1.80
0.73 1.59
0.41 0.89
0.3 0.65
0.21 0.46
0.09 0.2
0.03 0.07
Conclusion Having performed the investigation, the following conclusions are: As predicted, the longer in length the bigger the resistance for example at 5cm the resistance is 0.52 Ω and 50cm the resistance was 3.96 Ω. This can be clearly said for the 1st,2nd and average
results
The electrons didn't collide as much in the shorter wire because there was less time to do so, this leads to less resistance.
The wire show a strong trend of a straight line, i.e. the length of the wire is shown to be nearly proportional to the resistance double the length and the resistance doubles.
The overall resistance of the three results don't differ considerably.
Evaluation
In my Investigation I could of done more tests too make. My results more consistent. My Method could have been better, the wire was lose in some places making the results not as accurate.