The basic law that defines the relationship between voltage, current and resistance is the “Ohm’s Law”. It is known as the “V = I × R” formula. This tool allows you to enter two of these three parameters, and calculate the third value and power value instantly.
What is Ohm’s Law and by which formula is it expressed?
Ohm’s Law defines the relationship between voltage (V), current (I) and resistance (R) in a circuit. Formula: V = I × R. This basic law is the starting point for the analysis of electrical circuits.
How to calculate if one of the voltage, current and resistance is unknown?
In which areas is Ohm's Law used?
It is often used in electronic circuit design, power electronics, automotive systems, home electronics, LED calculations and battery systems. It is the basic principle of electrical engineering.
Does Ohm’s Law also apply in AC circuits?
Yes, but only for resistive loads. Additional parameters such as impedance and phase angle are also taken into account in AC circuits. In such cases, the extended Ohm's Law is used.
How is the circuit affected when the resistance is zero?
When the resistance is zero (short-circuit condition), the current theoretically becomes infinite, and this causes the fuse to blow or the circuit elements to burn out. Therefore, the resistance should not be too close to zero.
Why is an Ohm’s Law calculator used?
It provides a practical and fast solution against manual calculation errors. When the voltage, current or resistance is unknown, it allows the user to find the related values in no time.
Why are units important in Ohm's Law calculations?
The voltage is in volts (V), the current is in amperes (A) and the resistance is in ohms (Ω). Mixing different units (e.g. milliampere, kilohm) can result in calculation errors.
How is Ohm's Law used for LED circuit design?
To calculate a suitable resistance value for the LED, the following formula is usually applied: R = (V_source - V_led) / I_led. In this way, damage to the LED is avoided.
Can power (watts) be calculated with Ohm's Law?
How is Ohm's Law applied in circuits containing multiple components?
For series-connected resistors, the total resistance is summed up, while for parallel-connected resistors their “inverts” are summed up. Ohm's Law is applied to these total values and circuit analysis is performed.
