\[Q=C_mV_m\]
Variables
Qelectric charge stored in the membrane (C)
Cmmembrane capacitance (F)
Vmmembrane potential (V)
Description
What is this formula?
This formula calculates the electric charge stored across a biological membrane modeled as a capacitor. Cell membranes separate charges between the intracellular and extracellular environments.
When to use it
Use this formula in electrophysiology and cellular biophysics when analyzing membrane charging, action potentials, or electrical properties of cells.
Example
A membrane has:
Cm=1.0×10^-6 F
Vm=0.07 V
Formula:
Q=Cm*Vm
Substitution:
Q=(1.0×10^-6)*(0.07)
Result:
Q=7.0×10^-8 C
The membrane stores approximately 70 nC of charge.
Applications
- Neuron membrane modeling
- Cardiac electrophysiology
- Cellular bioelectricity
- Action potential analysis
- Biophysical membrane studies