MHT CET · Physics · Electrostatics
Three charges each of magnitude \(3 \mu \mathrm{C}\), are placed on the vertices of an equilateral triangle of side 6 cm . The net potential energy of the system will be nearly \(\left[\frac{1}{4 \pi \epsilon_0}=9 \times 10^9\right.\) SI unit \(]\)
- A \(1 \cdot 4 \mathrm{~J}\)
- B \(2 \cdot 7 \mathrm{~J}\)
- C \(4 \cdot 1 \mathrm{~J}\)
- D \(8 \cdot 2 \mathrm{~J}\)
Answer & Solution
Correct Answer
(C) \(4 \cdot 1 \mathrm{~J}\)
Step-by-step Solution
Detailed explanation
\(U_{net} = 3 \times \frac{1}{4 \pi \epsilon_0} \frac{q^2}{r}\) \(U_{net} = 3 \times (9 \times 10^9) \times \frac{(3 \times 10^{-6})^2}{0.06} = 4.05 \mathrm{~J} \approx 4.1 \mathrm{~J}\)
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