A capacitor is connected in an electric circuit. When key is pressed, the energy density at a distance 3.5 m from the source will be (in joule/m3)
Answer & explanation
Correct answer: option 4
Energy density at 3.5 m is given by
u = $\frac{1}{2} \varepsilon_0 E_{m}^2$
$=\frac{1}{2} \times 8.85 \times 10^{-12} \times(62.6)^2$
= 1.73 × 10–8
Hence the correct answer will be (D)