A uniformly charged ring of radius R has total charge Q. The electric field at a point on its axis at distance R from the center is:
Correct answer: C. kQ/(2√2R²)
- A. kQ/(2R²)
- B. kQ/(√2R²)
- C. kQ/(2√2R²)
- D. Zero
Explanation
For a charged ring, the electric field on the axis at distance x is E = kQx/(R² + x²)^(3/2). At x = R, E = kQR/(R² + R²)^(3/2) = kQ/(2√2R²). This is a hard-level question due to themathematical derivation.
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