Voltage drop

From Electronics Wiki

Electronic devices drop voltage in different scenarios. Dropping voltage refers to the amount of voltage change that can be found, by measuring potential before and after a device.

[edit] Resistors

If two resistors are in line with each other, a voltage can be found between them. e.g.: with a ten volt power supply, two 1 Ohm resistors are connected together in series across the power supply. Ohm's law states that 5 amperes of current runs through the whole circuit. Using Ohm's law again, you can find that each resistor drops 5 volts.

Ohm's law

Total current

Voltage drop over resistor

[edit] Capacitors

Capacitors have two different basic scenarios when dealing with voltage drop. An unchanging current scenario, and a changing current scenario. Capacitors in an unchanging current scenario act exactly as a resistor would, except their resistance is extremely high, and varies per capacitor. A capacitor in a voltage changing scenario will drop voltage due to this rule. , f being the frequency of the voltage change, and C being the capacitor's value.