• 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

Factors affecting Resistance.

Extracts from this document...

Introduction

Factors affecting Resistance

Plan:

     The Task of this investigation is to find out the factors that affect the resistance of a wire.

This will be done by performing experiments that try and investigate different proposed factors and to see whether they affect the resistance.

Resistance is the force, which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around the circuit. Resistance is measured in ohms. A resistor has the resistance of one ohm if a voltage of one volt is requires to push the current of one amp through it.
Resistance occurs when the electrons travelling along the wire collide with the atoms of the wire.
These collisions slow down the flow of electrons causing resistance. Resistance is a measure of how hard it is to move the electrons through the wire.
Wire length: If the length of the wire is increased then the resistance will also increase as the electrons will have a longer distance to travel and so more collisions will occur. Due to this, the length increase should be directly proportional to the resistance increase.      

This tells me that the voltage measures the amount of energy used up in getting each coulomb of charge through the wire. The units of volts are the same as joules per coulomb. Therefore, Ohms law says the more resistance means more energy used to pass through the wire. Resistance is a measure of how much energy is needed to push the current through something.

...read more.

Middle

2

10

0.7

0.2

2.9

15

0.7

0.2

3.5

20

0.8

0.15

5.3

25

0.85

0.1

8.5

30

0.875

0.1

8.75

35

0.9

0.1

9

40

0.9

0.1

9

45

0.9

0.1

9

50

0.9

0.1

9

55

0.9

0.1

9

60

0.9

0.1

9

65

0.9

0.07

12

70

0.9

0.075

12

75

0.9

0.07

12

80

0.9

0.075

12

85

0.9

0.07

12

90

0.9

0.075

12

95

0.9

0.07

12

100

Observation

The results from my experiment, does have a relationship with the length of the wire, but its not necessarily in direct proportion to the length of the wire.

For example: Between 5-40cm of wire, the resistance is about what I expected, it is always increasing because the longer the wire the more atoms and so the more likely the electrons are going to collide with the atoms.

Between 40-65cm of wire, the resistance stays at a constant 9 ohms. And between 70-100cm of wire it has a resistance of 12 ohms. This could be because only 12v was travelling through the wire and therefore wasn’t powerful enough to change the resistance after a certain point. One thing, which is unknown, is the resistance goes up to 9 ohms and suddenly jumps to 12 ohms. This could be because of inaccurate results as the experiment was only taken once.

Analysis:

        Through my experiment and observations. I have found out that the resistance isn’t to direct proportion to the length of the wire, because this would mean, 30cm of wire = resistance of 8.5 ohms. So 60cm of wire would = resistance of 17ohms.

...read more.

Conclusion

Apparatus for future experiments:

  • Digital Voltmeter, and Ammeter. This would give very accurate results
  • Selection of wire, thicker wire with a higher voltage going into the wire, may give an more accurate result.
  • Higher voltage power pack, on my graph I found that my prediction seemed to be correct at the beginning, but went out of the proportion later on. I think this could have something to do with the voltage, as it’s responsible for the resistance in the first place. A power pack, which goes up to 30 volts, would be good.

Supporting my conclusion:

        I have said this under the Analysis, but here it is again. I think that my results could be suitable to confirm my prediction and support a conclusion. However, the results I would have to double-check, as it doesn’t match my prediction. I know that my prediction is correct because outside resources (Textbooks and Britannica) say that ‘the length increases in direct proportion to the resistance. ´

The experiment is repeatable, by using the method, but factors like temperature, length of wire, Diameter or thickness, and the type of metal affect the resistance so these factors have to remain constant throughout the next experiment.


By Alex Barber 10RA

...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

    The factors affecting the resistance of a metalic conductor.

    4 star(s)

    However to verify my findings, I calculated the value of R from my graph and found: > 0.4mm Gradient = 0.52 - 0.49/1.4 - 1.3 = 0.3 Therefore; R = 1/0.3 = 3.3 > 0.56mm Gradient = 0.49 - 0.42/1.4 - 1.2 = 0.07/0.2 = 0.35 Therefore; R =1/0.35 =

  2. Physics GCSE Coursework:Factors affecting the resistance of a wire

    Therefore the equation is: "y=mx" I measured the constant gradient of my graph to be: However the gradient is usually measured as ?/mm, therefore: 0.106 / 10 = 0.0106 ?/mm After looking back at the equation that linked the resistance of a wire with its resistively length and area, which

  1. An in Investigation into the Resistance of a Wire.

    The results should be the same or nearly the same. The resistivity of Eureka constantan (quote from the Understanding Physics for Advanced Level by Jim Breithaupt) is 5.0 � 10-7. To do this I will use the formula above. An example is show below the rest of the working is show in a table after the example.

  2. Discover the factors affecting resistance in a conductor.

    Focus on getting a good diameter. Worry about the length afterwards.) 3) Once the putty is at the correct length and diameter, connect the two 2p coins to either end of the putty (making sure they are attached to the crocodile clips.

  1. Resistance of a Wire Investigation

    If the temperature is too cold then temperature becomes a limiting factor and the enzymes will stop working. Light As chlorophyll uses light energy to perform photosynthesis; it can only do it as fast as the light is arriving. Chlorophyll only absorbs the red and blue ends of the visible

  2. The aim of this investigation is to investigate the factors affecting the resistance of ...

    Resistors are often colour coded by three or four colour bands that indicate the specific value of resistance. Some resistors obey the Ohm's law, which states that the current density is directly proportional to the electrical field when the temperature is constant.

  1. An investigation into the factors affecting the resistance of a wire.

    I can now work out the resistance using the current and Voltage: R=V/I (ohms law) R - resistance in ohms (?? ohms) V - voltage (volts) I - current (amperes) I have discovered the circuit itself can resist the flow of particles if the wires are either very thin or very long.

  2. Factors affecting Resistance of a wire

    Potential difference is what "pushes" electrons around a circuit. When a wire has more electrons, for the same voltage it produces less current, meaning that there is more resistance. For example, say 6V are being put through a wire, and it produces a current of 3A, we can work out the resistance of this wire by using the formula V/I.

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