Introduction
Ohm's Law is one of the most important rules in electricity. It shows how voltage, current, and resistance are connected. The formula is simple: V = I × R. This means voltage (V) equals current (I) multiplied by resistance (R). If you know any two of these values, you can find the third one. This Ohm's Law Calculator solves the equation for you. Just enter two values, and the calculator will solve for the missing one. This tool makes it quick and easy to get the answer you need.
How to Use Our Ohms Law Calculator
Enter any two of the three values below, and the calculator will find the missing one using Ohm's Law (V = I × R).
Voltage (V): Enter the voltage in volts. This is the electric pressure that pushes current through a circuit. Leave this blank if you want the calculator to find it for you.
Current (I): Enter the current in amps. This is the flow of electric charge moving through the circuit. Leave this blank if you want the calculator to solve for it.
Resistance (R): Enter the resistance in ohms. This is how much the circuit slows down the flow of current. Leave this blank if you want the calculator to figure it out.
Understanding Ohm's Law
Ohm's Law is one of the most important rules in electricity. It describes the relationship between three things: voltage, current, and resistance. The formula is simple: V = I × R. This means voltage (V) equals current (I) multiplied by resistance (R).
What Do These Terms Mean?
Voltage is the force that pushes electric charges through a wire. It is measured in volts (V). Think of it like water pressure in a hose. The higher the pressure, the harder the water pushes through.
Current is the flow of electric charges through a conductor. It is measured in amperes (A), often called "amps." Using the water analogy, current is like the amount of water flowing through the hose.
Resistance is how much a material opposes the flow of current. It is measured in ohms (Ω). A thin hose would resist water flow more than a wide one, and resistance works the same way in a wire.
How Ohm's Law Works
If you know any two of the three values, you can always find the third. For example, if you know the voltage and resistance, you can find the current by using I = V ÷ R. If you know the current and resistance, you can find the voltage by using V = I × R. And if you know the voltage and current, you can find the resistance by using R = V ÷ I.
Why Ohm's Law Matters
Ohm's Law is used every day by electricians, engineers, and students. It helps people design safe circuits, choose the right parts, and troubleshoot electrical problems. Ohm's Law is the foundation you need to understand, from a simple LED circuit to a complex electrical system. It was named after German physicist Georg Simon Ohm, who published his findings in 1827.
Related Physics Concepts
Understanding Ohm's Law becomes even more powerful when combined with other fundamental physics principles. Power is closely tied to voltage and current (P = V × I), while energy works in different contexts as kinetic energy or potential energy.