3.7.3.1
A charged sphere acts as a point charge for an external observer
Electric Fields & Potential — AQA A-Level Physics
- A uniform spherical conductor has its chargeA property of matter that causes it to experience a force in an electromagnetic field. Measured in coulombs (C). distributed evenly on its surface.
- For any point outside the sphere, the chargeA property of matter that causes it to experience a force in an electromagnetic field. Measured in coulombs (C). can be treated as if it is concentrated at the centre.
- The electric field lines around a charged sphere are identical to those around a point chargeA property of matter that causes it to experience a force in an electromagnetic field. Measured in coulombs (C)..
- Positive sphere: field lines point radially outward.
- Negative sphere: field lines point radially inward.
- Air is treated as a vacuum in Coulomb's lawThe electrostatic force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. calculations.