Q 12-02-032NEETJEE MainMedium
The energy density in the electric field between the plates of a capacitor where the field is $10^5$ V/m is ($\epsilon_0 = 8.85 \times 10^{-12}$ F/m)
Answer: (A) $0.044\ \text{J/m}^3$
Concept. $u = \dfrac12\epsilon_0E^2$.
Step 1. Substitute. $0.5 \times 8.85 \times 10^{-12} \times 10^{10} \approx 0.044\ \text{J/m}^3$.
Answer. $0.044\ \text{J/m}^3$ (Option A).
Solution by Sreeraj P, M.Sc Physics