How is work done in electrical systems calculated?

Work done in electrical systems is calculated using the formula: Work Done (W) = Voltage (V) × Charge (Q).

In more detail, work done in an electrical system refers to the energy transferred when an electric charge moves through a potential difference (voltage). The formula W = V × Q helps us understand this relationship. Here, 'W' stands for work done or energy transferred, measured in joules (J). 'V' represents the potential difference or voltage, measured in volts (V), and 'Q' is the electric charge, measured in coulombs (C).

To break it down, voltage is the measure of the electrical potential difference between two points in a circuit. It tells us how much energy per unit charge is available to move electrons from one point to another. Charge, on the other hand, is a property of matter that causes it to experience a force when placed in an electric field.

For example, if you have a battery with a voltage of 9 volts and it moves a charge of 2 coulombs through a circuit, the work done can be calculated as follows:
\[ W = V \times Q \]
\[ W = 9 \, \text{V} \times 2 \, \text{C} \]
\[ W = 18 \, \text{J} \]

This means 18 joules of energy are transferred by the battery to move the charge through the circuit.

Understanding this concept is crucial in GCSE Physics as it helps explain how electrical devices consume energy. For instance, when you switch on a light bulb, the electrical energy is converted into light and heat energy, and the amount of electrical work done can be calculated using the voltage of the power supply and the charge that flows through the bulb. This fundamental principle is key to analysing and designing electrical circuits and systems.