Summary
Electric current is the flow of charge carriers, measured in amperes (A). It is defined as the rate of flow of charge, with charge measured in Coulombs. Current flows from the positive to the negative terminal in conventional terms, opposite to electron flow.
- Electric Current — the flow of charge carriers, measured in amperes (A). Example: Current in household wiring.
- Conventional Current — flow of positive charge from positive to negative terminal. Example: Opposite to electron flow.
- Charge — measured in Coulombs, it is the quantity of electricity. Example: Q = I * t, where Q is charge, I is current, and t is time.
- Quantization of Charge — charge comes in discrete units. Example: A single electron has a charge of approximately -1.60 × 10^-19 C.
- Drift Speed — average speed of charge carriers through a conductor. Example: Affects the current in a conductor.
Exam Tips
Key Definitions to Remember
- Electric Current: The flow of charge carriers, measured in amperes.
- Conventional Current: Flow of positive charge from positive to negative terminal.
- Quantization of Charge: Charge comes in discrete units.
Common Confusions
- Confusing the direction of conventional current with electron flow.
- Misunderstanding the relationship between charge, current, and time.
Typical Exam Questions
- What is the formula for calculating charge? Q = I * t, where Q is charge, I is current, and t is time.
- How does conventional current differ from electron flow? Conventional current flows from positive to negative, opposite to electron flow.
- What is the charge of a single electron? Approximately -1.60 × 10^-19 C.
What Examiners Usually Test
- Understanding of the direction and definition of conventional current.
- Ability to calculate charge using the formula Q = I * t.
- Knowledge of the quantization of charge and its implications.