Electricity & Magnetism
Capacitors in Series
Equivalent capacitance for series connection.
Variables
CeqF
Equivalent capacitance
Total capacitance
In SI units: A²·s⁴/(kg·m²)
Allowed values: greater than 0
C₁F
Capacitance 1
First capacitor
In SI units: A²·s⁴/(kg·m²)
Allowed values: greater than 0
C₂F
Capacitance 2
Second capacitor
In SI units: A²·s⁴/(kg·m²)
Allowed values: greater than 0
Derivation
Same charge: V = Q/C₁ + Q/C₂.
Your notes
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Check value
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- C₁ = 2 F (Capacitance 1)
- C₂ = 3 F (Capacitance 2)
Result: Ceq = 1.2 F
Where this formula is listed
- Electricity & Magnetism formulas, under Capacitance, alongside Parallel Plate Capacitor, Capacitor Energy, RC Time Constant, Capacitor with Dielectric and Energy Density (Electric Field).
- In the electricity & magnetism list it comes after Capacitor Energy and before Capacitors in Parallel.
- Electricity & Magnetism formula sheet, one of 48 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Capacitors in Series formula?
Capacitors in Series is written 1/C_eq = 1/C₁ + 1/C₂ + ... Equivalent capacitance for series connection. It belongs to Electricity & Magnetism, under Capacitance.
What are the units in 1/C_eq = 1/C₁ + 1/C₂ + ...?
In SI units, C_e q is equivalent capacitance, measured in A²·s⁴/(kg·m²); C₁ is capacitance 1, measured in A²·s⁴/(kg·m²); C₂ is capacitance 2, measured in A²·s⁴/(kg·m²).
How is the Capacitors in Series formula derived?
Same charge: V = Q/C₁ + Q/C₂. The result is 1/C_eq = 1/C₁ + 1/C₂ + ...