A point charge is a hypothetical object of negligible size. A 'test' charge is a point charge that does not affect the field it is in i.e. its own field is too small to change the field being measured.The electric field surrounding a point charge is radial. The equipotentials are concentric circles with the charge Q at the centre.The electric field strength due to a point charge Q is given by E = kQ/r2
Point Charges
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Specification: OCR Physics A (H556), A-level, 6.2.1 Point and spherical charges and 6.2.2 Coulomb's law. Topic: Electric Fields.
Key terms in this lesson
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More in Electric Fields
- Van de Graaf generator
- Electric Potential
- Equipotentials
- Potential gradient
- The Force between Two Charged Objects
- Coulombs Law
- Electric Field Strength
- Electric Potential
All 17 lessons in Electric Fields · All OCR A-level Physics topics