TS EAMCET · Physics · Electrostatics
Three point charges \(1 \mathrm{C},-2 \mathrm{C}\) and \(-2 \mathrm{C}\) are placed at the vertices of an equilateral triangle of side 1 metre. The work done by an external force to increase the separation of the charges to 2 metre in joule is ( \(\varepsilon_0=\) permittivity of air)
- A \(\frac{1}{4 \pi \varepsilon_0}\)
- B \(\frac{1}{8 \pi \varepsilon_0}\)
- C \(\frac{1}{16 \pi \varepsilon_0}\)
- D \(zero\)
Answer & Solution
Correct Answer
(D) \(zero\)
Step-by-step Solution
Detailed explanation
Work done by the external force must be zero.
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