The Uniform Field
Part of the Electricity and Magnetism section of Coddy's Physics journey. Lesson 7 of 51.
A large charged plate makes a uniform field: the same everywhere near it. With σ = Q / A its charge per square metre:
E = σ / (2ε₀)
on each side, away from a positive plate. ε₀ = 8.85 × 10⁻¹² C²/N·m².
Two plates with equal and opposite charges: between them the two fields add, outside they cancel.
E = σ / ε₀
Challenge
Two parallel plates, each of area 0.01 m², carry +8.85 nC and −8.85 nC. How strong is the field E between them?
Try it yourself
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Electricity and Magnetism
2The Electric Field
The Electric FieldField of Several ChargesThe Uniform FieldA Charge in a Uniform FieldRecap - Stopping a Proton3Energy and Potential
Electric Potential EnergyElectric PotentialField and PotentialRecap - Accelerating Ions6Current and Resistance
Current and VoltageResistance and Ohm's LawSeries and ParallelElectric PowerRecap - Fairy Lights9Capacitors in Circuits
A Capacitor in a CircuitCharging a CapacitorDischarging a CapacitorRecap - Defibrillator