A parallel plate capacitor stores charge, and thus, stores energy in the form – [Free] B38
A parallel plate capacitor stores charge, and thus, stores energy in the form of electric potential energy. The total energy stored in a parallel plate capacitor does NOT depend on
Energy Stored in a Parallel Plate Capacitor
1. A parallel plate capacitor stores charge and thus stores energy in the form of electric potential energy. The total energy stored in a parallel plate capacitor does NOT depend on __________.
The energy stored in a capacitor is calculated using the following equivalent formulas:
U = (1/2) C V²
U = Q² / (2C)
U = Q² / (2C)
Where:
- U represents the energy stored in the capacitor
- C is the capacitance of the plates
- V is the potential difference across the plates
- Q is the magnitude of the charge stored
Key Insight:
Each expression involves the square of either voltage or charge, which means:
- Only the magnitude of voltage or charge affects the energy
- The sign (positive or negative) has no effect due to squaring
Example Demonstrations:
Reversing the applied voltage (from +V to –V) results in:
U = (1/2) C (–V)² = (1/2) C V²
The result remains unchanged, confirming polarity doesn’t matter.
Similarly, for charge reversal (–Q instead of +Q):
U = (–Q)² / (2C) = Q² / (2C)
Again, the stored energy remains unaffected by the sign.
✅ Final Answer: The total energy stored in a parallel plate capacitor does NOT depend on the sign (polarity) of the charge or voltage. It only depends on their magnitudes.