Year 13
Side B2b: Capacitors
Introduce capacitance, stored energy, and capacitor discharge behaviour.
Part of Year 13 CIE Physics 9702.
Topic Overview
What students will cover
This topic keeps the core capacitor ideas tightly grouped so you can move from basic definitions to stored energy and discharge graph interpretation.
You begin by defining capacitance and using C = Q / V. The next lesson connects stored energy to the area under a potential-charge graph and the standard capacitor energy equations. The sequence then moves into discharging through a resistor, using time constants and exponential decay graphs before practice and review.
Revision
Topic revision route
Use the generated links below to move from lesson review to retrieval practice, syllabus checks, and useful resources.
Recall vocabulary
Capacitance
charge stored per unit potential difference.
capacitor
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
charge
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
Potential difference
energy transferred per unit charge across a component.
stored energy
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
potential-charge graph
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
discharge
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
time constant
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
exponential decay
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
capacitor networks
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
capacitor discharge
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
current
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
practice
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
test
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
test review
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
corrections
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
feedback
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
capacitors
A definition has not been added for this term yet. Use the lesson sequence below to review where it appears.
Resource bank
- Lesson resources
- 4
- Topic resources
- 0
Open the relevant lesson first, then use its linked slides, worksheets, simulations, or practice tasks.
Syllabus CIE 9702 coverage in this topic
9 points across 6 lessons
Show details
CIE 9702 coverage in this topic
9 points across 6 lessons
19.1.1
define capacitance, as applied to both isolated spherical conductors and to parallel plate capacitors
19.1.2
recall and use C = Q / V
19.1.3
derive, using C = Q / V, formulas for the combined capacitance of capacitors in series and in parallel
19.1.4
use the capacitance formulas for capacitors in series and in parallel
19.2.1
determine the electric potential energy stored in a capacitor from the area under the potential–charge graph 1 1
19.2.2
recall and use W = 2 QV = 2 CV 2
19.3.1
analyse graphs of the variation with time of potential difference, charge and current for a capacitor discharging through a resistor
19.3.2
recall and use τ = RC for the time constant for a capacitor discharging through a resistor
19.3.3
use equations of the form x = x0 e –(t / RC) where x could represent current, charge or potential difference for a capacitor discharging through a resistor
Lessons
Lesson sequence
Open lesson pages for summaries, objectives, notes, and linked resources. Test lessons stay locked for now.
Lesson
01Capacitors and Capacitance
Introduce capacitance and capacitor combinations in series and parallel.
Lesson
02Energy Stored in a Capacitor
Use potential-charge graphs and equations for energy stored in a capacitor.
Lesson
03Discharging a Capacitor
Analyse capacitor discharge graphs, time constant, and exponential decay equations.
Lesson
04Practice
Consolidate capacitance, stored energy, and capacitor discharge calculations.
Lesson
05Test
Assess understanding of capacitance, stored energy, and capacitor discharge.
Lesson
06Review
Review the capacitor test and strengthen weak areas.