Electric Quantities

Electric quantities:

· Voltage or potential difference, V: is the difference between the electrical energy at two points in a circuit. The charge Q (Coulombs) always moves from the point where the energy is highest to the lowest point. Unit: Volts (V)

· Current or intensity, I: is the number of electrons that pass through a specific point in a second. Unit: Amps (A)

· Resistance, R: is the opposition of the components of a circuit to the flow of the electric current. Unit: Ohms (Ω)

Sometimes we use multipliers of V, A, Ω. For example: millivolts (mV), milliamps (mA), kilohms (kΩ)

Measuring instruments:

• · Voltmeter: measures voltage (connected in parallel with the element)

• · Ammeter: measures current (connected in seriesl with the element)

• · Multimeter: measures different electric quantities, voltage, current, resistance ...

Ohm´s Law