BASIC ELECTRICAL MAGNITUDES: CURRENT, VOLTAGE AND RESISTANCE

• VOLTAGE: Voltage is the difference in electrical energy between two parts of a circuit. Voltage is measured in volts. The symbol for volts is V.

• CURRENT: Current is the amount of electric charge that flows through a circuit per second. Current is measured in amperes. The symbol for amperes is A.

• RESISTANCE: Resistance is the opposition that an electrical component offers to the flow of electricity through it. Resistance is measured in ohms (Ω).

HOW TO MEASURE ELECTRICAL MAGNITUDES USING A MULTIMETER

To solve the electrical circuits it is fundamental to measure their magnitudes. For this we will use the multimeter.

• VOLTAGE: To measure the voltage we will place the multimeter in parallel with the light bulb.

• CURRENT: To measure the current we will place the multimeter in series with the light bulb.

• RESISTANCE: To measure the resistance of an object you must make sure it has no voltage. Disconnect it.

OHM’S LAW

As we have seen, the most basic magnitudes of electricity are voltage, current and resistance. Ohm's law shows a simple relationship between these three quantities, hence this law can be considered as the most basic law of electrical engineering. Ohm's law first appeared in the book written by Georg Simon Ohm (German) in 1827.