Ohm's Law
The flow of electric current is governed by Ohm's Law, which is a fundamental principle of electric circuits that describes the relationship between voltage, current, and resistance.
It was discovered and named after Georg Simon Ohm, a German physicist, in the 19th century.
According to Ohm's Law, the current flowing through a conductor is directly proportional to the voltage applied across it, and inversely proportional to the resistance of the conductor.
This relationship is expressed by the equation I = V/R
where I is the current in amperes, V is the voltage in volts, and R is the resistance in ohms.
This equation can be rearranged to solve for any one of the variables, given the values of the other two.
For example, if the voltage and resistance are known, the current can be calculated using
I = V/R.
Similarly, if the current and resistance are known, the voltage can be calculated using
V = IR.
To understand the significance of Ohm's Law, it is helpful to consider a simple electric circuit consisting of a battery, a resistor, and a switch.
When the switch is closed, a current flows through the circuit from the positive terminal of the battery to the negative terminal, passing through the resistor on the way.
The amount of current that flows is determined by the voltage of the battery and the resistance of the resistor, according to Ohm's Law.
If the resistance of the resistor is high, the current will be low, even if the voltage of the battery is high.
Similarly, if the resistance of the resistor is low, the current will be high, even if the voltage of the battery is low.
This relationship is important for designing and analyzing electric circuits, as it allows engineers and technicians to predict the behavior of a circuit based on its components and their properties.