PHYS345 Electricity and Electronics
Ohm's Law and Resistance
Simple circuit experiment -- with better quality graph
Definition of Resistance
If a material obeys the relationship above, over a wide range of voltages,
it is said to be ohmic.
Not all devices are ohmic, and fortuately so, or we would not have the
wonderful semiconductor-based devices to which we have become so accustomed.
However over the next few classes we will be considering resistors to be made from
The unit of resistance is volt/amp, known as an ohm, and represented by upper case omega.
Units of Resistance
Resistance controls the amount of current that results when voltage difference
is applied to a resistor.
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Last updated Sept. 2, 1998.
Copyright George Watson, Univ. of Delaware, 1998.