In simple terms, resistance is opposition to the flow of current. It can be explained in terms of the atomic structure of matter.
Resistance is defined as the ratio of potential difference through a conductor to the current flowing through it!
Key Concepts
Resistance is the ratio of V/I. The larger the resistance, the smaller the current you will have for a given power supply (e.g. battery).
Check out this PhET simulation!
Interestingly, once you have selected the resistor for your circuit, the speed of charges actually changes within the resistor... but which way?
Note that resistance is not a rate of change. It is merely a ratio of voltage to current. Therefore, it is not obtained using the gradient of a graph - just using the coordinates.
How much of Resistance have you understood?
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