Calculate the Potential Difference Across a Filament Lamp
What is the relationship between the resistance of a 24 W, 12 V filament lamp and the current flowing through it?
For currents up to 0.8 A, what is the constant value of the resistance?
How can we calculate the potential difference across the lamp when a current of 0.8 A flows through it?
For currents up to 0.8 A, the resistance of a 24 W, 12 V filament lamp has a constant value of 2.5 Ω.
The resistance of a 24 W, 12 V filament lamp is dependent on the current flowing through it. Specifically, for currents up to 0.8 A, the resistance remains constant at 2.5 Ω. This shows that the relationship between the resistance and current is linear and predictable within this range.
When a current of 0.8 A flows through the lamp, the potential difference across it can be calculated using Ohm's law. Ohm's law states that the potential difference (V) is equal to the current (I) multiplied by the resistance (R). In this case, with a resistance of 2.5 Ω and a current of 0.8 A, the potential difference can be calculated as follows:
V = IR = 0.8 A x 2.5 Ω = 2 V
Therefore, the potential difference across the lamp when a current of 0.8 A flows through it is 2 V. Understanding this relationship between current, resistance, and potential difference is crucial in electrical circuits and can help in troubleshooting and designing efficient systems.