COMEDK · Physics · 17. Electrostatics
Three point charges are located on a circular arc at A, B and C as shown in the figure below. The total electric field at the centre of the arc (0) is
- A \(15000 \mathrm{~NC}^{-1}\)
- B \(5000 \mathrm{~NC}^{-1}\)
- C \(20000 \mathrm{~NC}^{-1}\)
- D \(10000 \mathrm{~N} \mathrm{C}^{-1}\)
Answer & Solution
Correct Answer
(B) \(5000 \mathrm{~NC}^{-1}\)
Step-by-step Solution
Detailed explanation
\(r = 6.0\) cm \(= 0.06\) m, \(r^2 = 0.0036\) m\(^2\) \(E_A = E_B = \dfrac{(9 \times 10^9)(4.0 \times 10^{-9})}{0.0036} = 10000\) N/C (away from A and B) \(E_C = \dfrac{(9 \times 10^9)(2.0 \times 10^{-9})}{0.0036} = 5000\) N/C (towards C, since charge is negative) By symmetry, A…
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