WBJEE · Physics · Electrostatics
Four identical point masses, each of mass \(\mathrm{m}\) and carrying charge \(+\mathrm{q}\) are placed at the corners of a square of sides 'a' on a frictionless plain surface. If the particles are released simultaneously, the kinetic energy of the system when they are infinitely far apart is
- A \(\frac{q^{2}}{a}(2 \sqrt{2}+1) \times \mathrm{k}\)
- B \(\frac{\mathrm{q}^{2}}{\mathrm{a}}(\sqrt{2}+2) \times \mathrm{k}\)
- C \(\frac{q^{2}}{a}(\sqrt{2}+4) \times \mathrm{k}\)
- D \(\frac{q^{2}}{a}(\sqrt{2}+1) \times \mathrm{k}\)
Answer & Solution
Correct Answer
(C) \(\frac{q^{2}}{a}(\sqrt{2}+4) \times \mathrm{k}\)
Step-by-step Solution
Detailed explanation
Hint: Hint \(: \mathrm{KE}_{i}+\mathrm{PE}_{\mathrm{i}}=\mathrm{KE}_{\mathrm{f}}+\mathrm{PE}_{\mathrm{f}}\)…
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