Electrostatics Question 114
Question: A charge of $ 40\mu C $ is given to a capacitor having capacitance $ C=10\mu F $ . The stored energy in ergs is [CPMT 2002]
Options:
A) $ 80\times {{10}^{-6}} $
B) 800
C) 80
D) 8000
Show Answer
Answer:
Correct Answer: B
Solution:
$ U=\frac{Q^{2}}{2C}=\frac{{{(40\times {{10}^{-6}})}^{2}}}{2\times {{10}^{-6}}\times 10}=\frac{16\times {{10}^{-10}}}{2\times {{10}^{-5}}}=8\times {{10}^{-5}}J $
$ =8\times {{10}^{-5}}\times 10^{7}=800erg $
