What happens with current when we increase the voltage across a conductor?
Answers
Answer:
Ohm's law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change.
That depends on what components are used n the circuit. Ohm’s law says V=IR, which implies that if the resistance remains fixed, a rise in voltage would similarly cause a rise in current. In the simplest textbook examples it’s assumed that these factors can be set to fixed values and then varied at will.
However, there are many kinds of devices that do not strictly behave according to Ohm’s law and where the resistance may change based upon other factors. For example, some devices have variable resistance depending on the temperature of the components. In some devices the resistance may rise, in others it may fall. Since the flow of current tends to make components hotter, then in the case of falling resistance with increased temp there is a risk of “thermal runaway”. As the resistance drops if the resistance drops more current can flow, causing more heat to be generated, and so on, until the temperature reaches a point that destroys the device.
Just be careful not to assume that all circuits behave strictly according to Ohm. :-)
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