Topic study hub
Current electricity
Study Current electricity as part of Electricity for AQA A-Level Physics 7408. This topic hub connects the approved learning objectives to flashcards, MCQs, exam-style questions, answer explanations, revision notes, key terms, common mistakes, exam tips, and mini practice tests where those assets are published. Use the overview to separate definitions, equations, data analysis, graph interpretation, practical reasoning, and conceptual explanations before moving into the practice tools. For Current electricity, pay close attention to units, assumptions, evidence and boundary distinctions so answers stay specific to the exact A-Level Physics context.
0
Objectives
10
Flashcards
10
Questions
90 min
Study time
Choose a revision tool
Start revising Current electricity
Syllabus checklist
What you need to know
0 objective pages available
Basics of electricity4 objectives
- Use current as the rate of flow of charge.
- Use potential difference as energy transferred per unit charge.
- Apply Ohm's law to suitable conductors.
- Use electrical power and energy equations in circuit contexts.
Current-voltage characteristics4 objectives
- Interpret I-V graphs for ohmic conductors.
- Explain the I-V characteristic of a filament lamp.
- Explain the I-V characteristic of a diode.
- Distinguish ohmic and non-ohmic behaviour.
Resistivity4 objectives
- Define resistivity as a material property.
- Use R = rho L / A in calculations.
- Explain how length and cross-sectional area affect resistance.
- Required practical 5: determine the resistivity of a wire.
Circuits4 objectives
- Apply conservation of charge to current in circuits.
- Apply conservation of energy to potential differences in circuits.
- Calculate total resistance in series and parallel combinations.
- Analyse circuits using meter readings and component values.
Potential divider4 objectives
- Explain how a potential divider produces a chosen output voltage.
- Calculate output voltage in potential divider circuits.
- Describe how LDRs and thermistors affect potential divider output.
- Apply potential dividers to sensing and control contexts.
Electromotive force and internal resistance4 objectives
- Define electromotive force as energy supplied per unit charge.
- Explain terminal potential difference and lost volts.
- Use emf and internal resistance relationships in calculations.
- Required practical 6: investigate emf and internal resistance of a cell.
Key terms
Exam tips
- Understanding Current Flow: Remember that current (I) is defined as the rate of flow of charge (Q) over time (t). Use the formula Q = I x t to calculate charge flow in circuits.
- Understanding Potential Difference: Use the named electrical quantity first, then write the matching equation, substitute values with units, and finish by explaining what the answer means in Current electricity. Avoid swapping current, charge, potential difference, resistance, power, and energy because those changes alter both the formula and the unit.
Common mistakes
- Misunderstanding Current Flow: To clarify, remember that current (I) is defined as the flow of charge (Q) per unit time (t). The formula is I = Q / t. For example, if 10 coulombs of charge flow in 2 seconds, then I = 10 C / 2 s = 5 A. Thus, current is measured in amperes (A), indicating the rate of flow, not the total charge.
- Understanding Potential Difference: Potential difference is defined as the energy transferred per unit charge, while energy transferred is the total energy used in a circuit. Potential difference applies when discussing how much energy is available to move charge through a circuit, whereas energy transferred applies to the total energy consumed by components over time. Always remember that potential difference is a measure of energy per charge, not total energy.
Practice preview
- Which statement gives the clearest definition needed for Use Current As The Rate Of Flow Of?
- A student makes a mistake while revising Use Current As The Rate Of Flow Of. Which correction is most accurate?
- Which response best uses evidence or a diagram feature to support Use Current As The Rate Of Flow Of?
Continue by objective
Objectives are grouped by subtopic so students can jump straight to the exact skill they want to revise.
Related topics