• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13
  14. 14
    14
  15. 15
    15
  16. 16
    16
  17. 17
    17
  18. 18
    18
  19. 19
    19
  20. 20
    20

Physical - Circuit

Extracts from this document...

Introduction

Science Investigation Report        Daniel

                F5D

P                O                A                E                

6                6                6                4                24/30

image00.png

Name: Daniel Shih

Class: F5D

Teacher: Dr. Aravind

School: Kiangsu-Chekiang College International Section

Date: 30th November, 2006image01.png

Index

image02.png

Introduction

Planning – Aims, Variables, Fair Test, Prediction, Hypothesis

Planning – Apparatus, Procedure

Planning –Procedure of temperature, measurement, safe rules

Obtaining

Analyse – Table 1

Analyse – Table 2

Analyse – Table 3

Analyse – Table 4

Analyse – Table 5

Analyse – Table 6

Analyse – Table 7

Analyse – Table 8

Analyse – Compare and Contrast

Evaluation, Conclusion, Bibliography

image03.png

Introduction:

What is an electrical circuit?

An electrical network is an interconnection of electrical elements such as the resistors, inductors and switches. We use circuit to measure the voltage, and also the current of some conductors which can transfer the electricity. To design an electrical circuit, first we need to be able to predict the current and the voltage.

What is electrical resistance?

Electrical resistance is a measure of the voltage divided by the current flows in the electrical circuit. The unit of resistance Is Ohms,Ω. The quantity of resistance in an electric circuit determines the amount of current flowing in the circuit for any given voltage applied to the circuit. The way of measuring the resistance in a circuit is:

image05.png

“R” is the resistance of the object, measured in ohms.

“V” is the potential difference or the voltage across the object, measured in volts.

“I” is the current passing through the object, measured in amps

So what are the uses of electrical circuit?

        This is a test to find out the best conductor in metals, the higher the resistance, that means the better the metal could be used to pass the electrons through.

Also, the temperature of the metal will affect the amount of electrons flows at each time, by heating the metal up, it would expand and allows more resistance; so the temperature were low, it might can’t conduct electricity at all.

Planning:

Aims:

...read more.

Middle

20

0.3

3.4

0.3

3.5

0.3

3.45

25

0.35

3.4

0.35

3.4

0.4

3.4

30

0.4

3.2

0.4

3.1

0.4

3.1

Length (centimetres)

Voltage (Volts)

Current (amps)

Resistance (Ω)

5

0.1

3.5

0.0286

10

0.2

3.75

0.0533

15

0.25

3.62

0.0691

20

0.3

3.45

0.0890

25

0.37

3.4

0.1088

30

0.4

0.3.13

0.1278

image09.png

In this graph, we could see that the resistance of the wire were increasing as the length increases. This means constantan wire with diameter of 1.25mm can be use as a good conductor. It nearly occurred in a straight line if the resistance of length 5cm were higher a little bit.

Table 3: This table tells about the normal wires used in the experiment, Constantan wire with diameter of 0.90mm.

First Tried

Second Tried

Third Tried

Length (centimetres)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

5

0.2

3.5

0.1

2

0.1

2.1

10

0.2

1.8

0.1

1.8

0.1

1.8

15

0.2

1.8

0.1

1.75

0.2

1.75

20

0.25

1.7

0.25

1.8

0.2

1.7

25

0.3

1.7

0.3

1.7

0.3

1.7

30

0.4

1.7

0.35

1.7

0.35

1.7

Length (centimetres)

Voltage (Volts)

Current (amps)

Resistance (Ω)

5

0.13

2.5

0.052

10

0.13

1.8

0.0722

15

0.17

1.77

0.0960

20

0.18

1.73

0.1040

25

0.3

1.7

0.1765

30

0.37

1.7

0.2176

image10.png

In this table, I can see that the resistance weren’t stable. With the length of 20cm, this might because of the ammeter have some problem while we’re measuring. I believe if we have a chance to retry it over again, we should get better results as what we have expected.

Table 4: This table shows about the normal wires used in the experiment, Constantan wire with diameter of 0.90mm, however is longer than the one before. Error*

First Tried

Second Tried

Third Tried

Length (centimetres)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

35

0.7

2.6

0.7

2.7

0.7

2.8

40

0.5

2.5

0.7

2.6

0.7

2.6

45

0.5

2.5

0.4

2.6

0.4

2.5

50

0.8

2.2

0.8

2.3

0.8

2.3

55

0.9

2.3

0.9

2.3

0.9

2.4

60

1

2.3

0.9

2.4

1

2.4

Length (centimetres)

Voltage (Volts)

Current (amps)

Resistance (Ω)

5

0.7

2.7

0.26

10

0.64

2.54

0.26

15

0.44

2.54

0.18

20

0.8

2.27

0.36

25

0.9

2.34

0.39

30

1

2.37

0.43

image11.png

As the table shows above, the resistance of the length 5cm and 10cm were equal, and then it suddenly decreases. This shows there’s an error; I think it happened because we didn’t set our circuit in the correct positon.

Table 5: This table shows the details about normal wires used in the experiment, Constantan wire with diameter of 0.90mm, however is longer than the one before, retry.

First Tried

Second Tried

Third Tried

Length (centimetres)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

Voltage (Volts)

Current (amps)

35

0.4

1.6

0.4

1.6

0.45

1.6

40

0.45

1.6

0.45

1.6

0.5

1.6

45

0.5

1.5

0.5

1.6

0.5

1.55

50

0.55

1.5

0.55

1.5

0.55

1.5

55

0.6

1.5

0.6

1.5

0.6

1.5

60

0.6

1.45

0.6

1.5

0.6

1.45

Length (centimetres)

...read more.

Conclusion

Conclusion

In my own opinion, I believe this is quiet a nice experiment, and I also get some good results as well. I’ve found out that my prediction was correct, about the copper wire with a diameter of 90mm will transfer the least energy compare to the rest of the two.

        I also learned about the circuit of electricity, I could now tell how the current flowing was, and how it could be measured. By looking at the results I’ve got, I was really please, even though some mistakes happened in the experiment, but we still success to finish our experiment in the time limit, which is such a great thing to celebrate.

        Resistor can be use to protect the ammeter, this is a very useful apparatus; I know the ammeter was an important character in the circuit while measuring the resistance. So if the ammeter were damage cause of the flowing current were too high, this will be a very bad news for us. So take care of the equipment is another important thing I learn from this experiment.

        If I have a chance to repeat the experiment, I would be likely to set my circuit up just like this time, because there shall be less problems. And I might use the copper wire more often in the circuit, using copper wires it allows more current to pass through compare to the Nicrhome and Constantan wires, which might help in my future life.

Bibliography:

http://en.wikipedia.org/wiki/Series_and_parallel_circuits

http://www.circuitcity.com/ccd/home.do

...read more.

This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Electricity and Magnetism essays

  1. Marked by a teacher

    Investigate young's modulus behind Constantan and Copper.

    4 star(s)

    The property of the other elements is what makes an alloy stronger then a pure metal. Necking does not occur in metals, it is quite hard for it to occur, this is because there is no dislocation of atoms, which occur within the structure to make this, stronger, and hold its atoms together.

  2. Marked by a teacher

    Draw stress and strain graphs for the metal copper and the alloy constantan. Calculate ...

    4 star(s)

    so presence of nickel in copper) means that dislocations are filled in, and hence this makes it more difficult for the metal to slip making it less ductile. (Adapted from Advancing Physics AS Textbook page 116-117). In order to work out Young's modulus I will need to calculate the stress acting on the metal and alloy wires.

  1. Peer reviewed

    Investigation in resistance in wires

    5 star(s)

    the current, in recollection I believe I should have measured it in milliamps. For most of the others it wasn't much of problem because the gaps were large between each wire length, but as the wire got longer the lengths became closer and harder to tell apart when using amps.

  2. Free essay

    How the length of constantan wire affects the ressistance in a electrical circuit

    Voltmeter (v) volts Current (I) amps Resistance ? Ohms 10 2.1 3.61 0.58 20 2.77 2.4 1.15 30 2.64 1.8 1.46 40 2.77 2.4 1.15 50 2.9 1.05 2.76 60 3.47 1.01 3.43 70 3.51 0.88 3.98 80 3.7 0.81 4.56 90 3.75 0.77 4.87 100 3.79 0.64 5.92 Test 6 - Length (cm)

  1. Investigate the resistance of different wires and how at different lengths the voltage increases ...

    The following table shows the resistance and the temperature coefficient at 20oc of the four wires that I am investigating. Material Resistivity ? (ohm m) Temperature coefficient per degree C Conductivity ? x 107 /?m Copper 1.68 x10^-8 .0068 5.95 Manganin 48.2 x10^-8 .000002 0.207 Nichrome (Ni,Fe,Cr alloy)

  2. Resistance and Wires

    represents the value of the highest recording taken from the experiment, and the lower line represents the lowest value. The cross in between the two lines represents the mean result. This is the most accurate result, calculated by dividing the sum of each recording by the number of recordings.

  1. An experiment to find the resistivity of nichrome

    The difference between the two should be proportional according to my scientific knowledge. I predict that as the length increases, so does the resistance. I also predict that they will be proportional to one another, and that each 50cm reading shall be ten times bigger than each 5cm reading.

  2. Investigate one or more factors affecting the resistance of metal wires

    Steps 4 and 5 were repeated - each time I increased the wire length by 10cm until the length of the wire was 100cm, which was my last reading. (Note that I started taking readings at the shorter lengths of wire and gradually increased to the longer lengths because

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work