• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

You are to investigate the factors that affect the current through a light bulb.

Extracts from this document...

Introduction

You are to investigate the factors that affect the current through a light bulb.

Introduction:

My theory of current is that it is the rate at which charge flows around a circuit.

Current (I) =         Charge flowing (Q)

        Time (T)

Current (I) =         Power (P)        

        Potential Difference (V)

Factors that affect current are:        Voltage or ‘The potential difference’

        Resistance

        Amount of charge flowing

        Time

        The length/thickness of the wire

Electrical circuits:

An electrical cell has two terminals. The chemical reaction the cell makes the negative terminal electron rich and the positive terminal electron short. If the terminals are joined by a piece of conducting wire to make a circuit, then electrons flow between them. The electrons flow from the negative terminal to the positive terminal. This is called the electron current.

A conventional current, which is thought of as flowing from the positive to the negative has been used for many years. Since it flows from the positive to the negative:

The conventional current flows in the opposite direction to the electron current.

Volts:

The part of the electromotive force that

...read more.

Middle

0.24

not visible

0.3

0.09

0.09

0.09

0.27

not visible

0.4

0.1

0.09

0.09

0.28

not visible

0.5

0.1

0.1

0.1

0.3

not visible

0.6

0.11

0.11

0.11

0.33

not visible

0.7

0.11

0.12

0.11

0.34

Just Visible

0.8

0.12

0.12

0.12

0.36

visible

0.9

0.13

0.13

0.12

0.38

visible

1

0.15

0.14

0.14

0.43

visible

1.1

0.15

0.15

0.15

0.45

brighter

1.2

0.16

0.16

0.15

0.47

bright

1.3

0.17

0.16

0.16

0.49

bright

1.4

0.17

0.17

0.17

0.51

bright

1.5

0.18

0.18

0.18

0.54

bright

1.6

0.18

0.18

0.18

0.54

alot brighter

1.7

0.18

0.19

0.19

0.56

alot brighter

1.8

0.19

0.19

0.19

0.57

...read more.

Conclusion

This graph means that as the voltage increases so does the current increase, this is shown by the graph corrolation, and by the curvature of the graph indicating that more current is produced with less voltage.

A revised theory from this graph explaining my results and graph is that current seems to increase more than the amount of voltage put in. Creating a curved line.

I believe that my predictions were almost correct, yet now I can see that I made some elementary errors.

Evalutaion:

Advantages and Disadvantages of the experiment are that it went well under planning yet I failed to conclude in sufficient detail, I expected my results and these I gained from my scientific knowledge.

I believe that I could re do the experiment to gain more reliable results, and I have found that the graph shows that my earlier theories were correct. Indecating a well planned prediction.

Patterns in the graph are that the current goes up as the voltage is increased.

Annommalies, I don’t think I have found any anomalies in my graph though if I did find any I would expect to find out that they were caused by incorrect measurements of the results or problems with the equipment, etc.

Aaron Jessop

11H

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics 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 AS and A Level Electrical & Thermal Physics essays

  1. To Investigate How the Resistance of the Light Dependent Resistor Depends On the Current ...

    And the voltage in the circuit is equal toV2 plus the voltage of R2. The Voltage in the circuit keeps the same and the voltage of R2 increases, so V2 decreases. 2. I predict that the graph of the resistance of the LDR against to the current of the light

  2. How Does Voltage Affect Current

    This vibration of atoms can get in the way of passing electrons and therefore results in fewer electrons getting through and a higher resistance. Also, the reason the filament in the light bulb heats up and glows is because the electrons passing by at a normal speed will still knock into atoms.

  1. Sensors cwk. The aim of this coursework is to construct a potential divider circuit ...

    This law applies to light intensity; as we increase the distance of the light source from a given object (LDR) or point, the light intensity decreases. The relationship can be shown by the formula: where; I= light intensity & d= distance from object This just means that if we double the distance, the light intensity decreases by 1/4.

  2. Investigating The Characteristics Of A Light Bulb.

    9 volts: V/V I/A 1. 0.76 0.58 2. 1.13 0.68 3. 1.50 0.73 4. 1.95 0.81 5. 2.30 0.87 6. 3.46 1.05 7. 4.18 1.19 8. 4.85 1.23 9. 5.67 1.34 10. 6.45 1.65 I decided that I would turn the power supply to 12 volts, because I might find better results.

  1. To find the factors that affect the amount of E.M.F. being produced. The amount ...

    * Too much current can made the wire to melt causing smoke and fire therefore tried to use the current as low as possible. * When magnetizing the iron careful not to put your finger between them because your finger will either be squash or cut.

  2. To investigate the effects of two different variables on a solar cell output.

    You can vary this variable using a power pack, and it is also very easy to control with this equipment, therefore I will also measure this variable. I have therefore decided to test out variables 2 and 3. Hypothesis: When investigating the two variables I stated, I think that as

  1. Relationship between the current and voltage.

    As the resistance, of the, " wire wound resistor," will be a constant, I expect a straight line graph. There I also expect the resistors to be applicable to ohms law. This is, as the temperature of the resistors will be kept constant, as the voltage will not be very high.

  2. To find which of the circuits, shown below, are most suitable to measure a ...

    Prediction for Circuit Two: In these predictions I will be picking different resistances for the variable resistor, and then trying to calculate the resistance using the meter readings. In these calculation the resistance of the ammeter will be R2 for the resistor this will be R1.

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