Ohm’s law
Ohm’s law is a fundamental principle in electrical engineering that describes the relationship between electric current, voltage, and resistance.
The law states that the current passing through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them. Mathematically, Ohm’s law can be expressed as:
I = V / R
where I is the current in amperes, V is the voltage in volts, and R is the resistance in ohms.
In other words, if the voltage across a conductor is increased, the current through it will also increase provided the resistance remains constant. Similarly, if the resistance is increased, the current will decrease for a given voltage. Ohm’s law is useful in designing and analyzing electrical circuits, and is one of the fundamental laws in electrical engineering.
Ohm’s law states that the R in this relation is constant and independent of the current. If the resistance is not constant, the previous equation cannot be called Ohm’s law, but it can still be used as a definition of static/DC resistance. Ohm’s law is an empirical relation that accurately describes the conductivity of the vast majority of electrically conductive materials over many orders of magnitude of the current. However, some materials do not obey Ohm’s law; these are called non-ohmic.
Application of Ohm’s law
Ohm’s law is a fundamental principle of electrical engineering and is used in many practical applications. Here are a few examples:
- Circuit design: Ohm’s law is used extensively in the design of electrical circuits, where it helps engineers to determine the proper values of resistors, capacitors, and other components needed to achieve the desired current and voltage levels.
- Electrical safety: Ohm’s law is also used in the design of electrical safety systems, such as fuses and circuit breakers. These devices are designed to break the circuit when the current exceeds a certain level, which is determined by the resistance of the circuit.
- Power distribution: Ohm’s law is used to calculate the power dissipated in a circuit, which is important for power distribution systems. By knowing the voltage and current of a circuit, engineers can calculate the power consumed by the circuit and determine the proper size of wires, transformers, and other components needed for efficient power distribution.
- Electronics troubleshooting: Ohm’s law is also used in troubleshooting electrical problems in electronic devices. By measuring the voltage and current of a circuit, engineers can determine the resistance of the circuit and identify any faulty components or connections that may be causing problems.
Overall, Ohm’s law is a critical concept in electrical engineering and is used in a wide range of applications, from basic circuit design to complex power distribution systems.
