# Electric Resistance

on . Posted in Electrical Engineering

Electric resistance R is a measure of how much an object or substance opposes the flow of electric current through it.  In order to overcome the resistance and get the current to flow a higher voltage will be required. Resistance is measured in Ohms, represented by $$R$$ and has a symbols $$\Omega$$.  The resistance of an object depends on its size, shape, material, and temperature.

### Electric Resistance Index

The resistance of a material can be calculated using Ohm's Law, which states that the current flowing through a conductor is directly proportional to the voltage across it, and inversely proportional to its resistance.

### Electric resistance formula

$$R \;=\; V \;/\; I$$     (Electric Resistance)

$$V \;=\; R \; I$$

$$I \;=\; V \;/\; R$$

Symbol English Metric
$$R$$ = resistance $$\Omega$$ $$kg-m^2\;/\;s^3-A^2$$
$$V$$ = voltage $$V$$ $$kg-m^2\;/\;s^3-A$$
$$I$$ = current $$I$$ $$C\;/\;s$$

### Electric resistance formula

$$R \;=\; V^2 \;/\; P$$     (Electric Resistance)

$$V \;=\; \sqrt{ R \; P }$$

$$\ P \;=\; V^2 \;/\; R$$

Symbol English Metric
$$R$$ = resistance $$\Omega$$ $$kg-m^2\;/\;s^3-A^2$$
$$V$$ = voltage $$V$$ $$kg-m^2\;/\;s^3-A$$
$$P$$ = power $$P$$ $$kg-m^2\;/\;s^3$$

### Electric resistance formula

$$R \;=\; P \;/\; I^2$$     (Electric Resistance)

$$P \;=\; I^2 \; R$$

$$I \;=\; \sqrt{ P \;/\; R }$$

Symbol English Metric
$$R$$ = resistance $$\Omega$$ $$kg-m^2\;/\;s^3-A^2$$
$$P$$ = power $$P$$ $$kg-m^2\;/\;s^3$$
$$I$$ = current $$I$$ $$C\;/\;s$$

Tags: Electrical Resistance