The I-V characteristics of a resistor are observed to deviate from a straight line for higher values of current.Why??
- For normal range of values of current, the current through a resistor is directly proportional to the potential difference. Hence, the shape of the graph is a straight line whose slope is constant.
- But, for higher values of current, the current through a resistor is not exactly directly proportional to the potential difference due to excess temperature due to the heat energy produced in the resistor. This results the deviation of I-V characteristics from a straight line to curved shape.