Learn how to safely plan and carry out an investigation into current, voltage, resistance and Ohm's law.
Part of Combined SciencePrescribed practicals
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We can see from the graph that as the current increases the voltage also increases.
This agrees with our prediction.
In fact, since the line of best fit is a straight line through the origin, we can be even more precise.
We can say that the voltage across the wire is directly proportional to the current flowing through it.
As the voltage increases the current increases in direct proportion.
This is known as Ohm鈥檚 Law.
A conductor that obeys Ohm鈥檚 Law is called an ohmic conductor.
Copper or constantan wire are examples of ohmic conductors.
Current, voltage and resistance are related by the equation:
voltage V = current I x resistance R
V= IR
V = voltage in V
I = current in A
R = resistance in \(\Omega\)