What is electrical resistance measured in?

Electrical resistance is a measure of how much a material or electronic component impedes the flow of electric current. It is denoted by the symbol "R" and is measured in ohms (Ω). Resistance is caused by the collisions of electrons with atoms in a material, which generates heat and reduces the flow of current.

The resistance of a material is dependent on its physical properties, such as length, cross-sectional area, and temperature. In general, longer and thinner wires have higher resistance, while shorter and thicker wires have lower resistance. The temperature of a material can also affect its resistance, with most materials exhibiting an increase in resistance as temperature increases.

Resistance is an important parameter in electrical circuits as it determines the amount of current that can flow through a circuit for a given voltage. Components such as resistors are designed to have specific resistance values to control the flow of current and voltage in a circuit. 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, is commonly used to calculate and analyze electrical circuits.