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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

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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.

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