Ohm's Law, Resistance and Resistivity Ohm's Law: Ohm's Law states that the current flowing through a conductor is directly proportional to the voltage ap...
Ohm's Law:
Ohm's Law states that the current flowing through a conductor is directly proportional to the voltage applied across it and inversely proportional to the resistance present. In other words, I = V/R, where I is current, V is voltage, and R is resistance. This means that if you increase the voltage, the current will also increase, but if you increase the resistance, the current will decrease.
Resistance:
Resistance is a measure of how much opposition a conductor offers to the flow of current. It is defined as the ratio of the voltage applied to the current flowing through a conductor. The resistance of a conductor depends on its material properties, such as its length, width, and resistance to heat flow.
Resistivity:
Resistivity is another measure of how much a conductor opposes the flow of current. It is defined as the reciprocal of resistance. The resistivity of a conductor is equal to the inverse of its resistance.
Examples:
Ohm's Law: If you increase the voltage across a 12-volt battery, the current will also increase, but the resistance will remain the same. This means that the current will be 2 amps.
Resistance: A piece of copper wire has a resistance of 0.01 ohms. This means that if you apply a voltage of 12 volts to the wire, the current will be 1 amp.
Resistivity: A copper wire has a resistivity of 1.68 × 10^-8 ohms per meter. This means that if you apply a voltage of 12 volts to the wire, the current will be 0.75 amps.
By understanding these concepts, you can analyze and solve problems involving current, voltage, and resistance in various electrical circuits