Learn the basics of Electrical Engineering.

Kirchhoff's Voltage Law

Statement: The sum of voltage rise in any electrical circuit is equal to the sum of voltage drops in that circuit.

Consider an electrical source with a voltage source which connects with three resistors. R1, R2 and R3. The sum of voltage drops across these resistors is equal to the sum of the input voltage(voltage rise).

Here are a few examples of KVL which help you to learn it in a better way:

Example 1: A 15 V input source powers three resistors, having a series current of 2 mA flowing through them. Find the voltage across R3.

Step 1: Using Ohm's law find the voltage drop across the first resistor.
V = IR = 2 mA* 2 kohm = 4 V

Step 2: Applying KVL:
V_rise = V_drop
15 V = 4 V + 5 V + V_R_3
V_R_3 = 15 V - 5 V - 4 V = 6 V

Example 2: A 20 V source powers three series resistors. The wattage rating of the first one being 30 watts having a current of 3 A flowing through it. The second resistance has all parameters unknown. Whereas, the third one has a voltage drop of 5 V across it. Find all unknown voltages in the circuit.

Step 1: Using formulas P = VI, or V = P/I = 30 watt/3 A = 10 V

Step 2: Using KVL;
V_rise = V_drop;
20 V = 10 V + V_R_2 + 5 V
or V_R_2 = 15 V


  1. I think in the last line VR2=should be 5V not 15V

  2. The first example schematic shows a 2A current, in the calculation 2mA is used.

  3. In Example:2 VR2=5v not 15v

  4. As extra loads are associated, the all out current will increment, accordingly expanding the voltage drop across the basic impedances (R). high voltage diode manufacturer

  5. Albeit the capacitance, (C) of a capacitor is equivalent to the proportion of charge per plate to the applied voltage, it additionally relies upon the actual size and distance between the two conductive plates. For instance, on the off chance that the two plates where bigger or different plates where utilized, there would be more surface region for the charge to aggregate on giving a higher worth of capacitance. power mosfet manufacturer