Electrostatics Question 396
Question: What is the potential energy of the equal positive point charges of $ 1\mu C $ each held 1 m apart in air [AMU 1999]
Options:
A) $ 9\times {{10}^{-3}}J $
B) $ 9\times {{10}^{-3}}eV $
C) $ 2eV/m $
D) Zero
Show Answer
Answer:
Correct Answer: A
Solution:
By using $ U=9\times 10^{9}\frac{Q _{1}Q _{2}}{r} $
therefore $ U=9\times 10^{9}\times \frac{{{10}^{-6}}\times {{10}^{-6}}}{1}=9\times {{10}^{-3}}J $