COMEDK · Physics · 17. Electrostatics
Three point charges \(-1 C,+1 C,+1 C\) are placed at points \(\mathrm{A}, \mathrm{B}, \mathrm{C}\) respectively of a triangle ABC . What is the total potential energy of the system? [given \(\mathrm{AB}=\mathrm{AC}=6 \mathrm{~cm}\) and \(\mathrm{BC}=3 \mathrm{~cm}\) ]
- A 0 J (Zero joule)
- B \(4.5 \times 10^{13} J\)
- C \(3 \times 10^{13} J\)
- D \(6 \times 10^{13} J\)
Answer & Solution
Correct Answer
(A) 0 J (Zero joule)
Step-by-step Solution
Detailed explanation
The potential energy \(U\) of a system of point charges is given by the sum of the potential energies of all pairs of charges: \(U = k \left( \dfrac{q_A q_B}{r_{AB}} + \dfrac{q_B q_C}{r_{BC}} + \dfrac{q_A q_C}{r_{AC}} \right)\), where…
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