A 1300-N/C electric field in a polyethylene dielectric, $K = 2.3$ , has an energy density of
A) $1.7 \times 10 ^ { - 5 }$ J/m $3$
B) $2.9 \times 10 ^ { - 7 }$ J/m $3$
C) $5.6 \times 10 ^ { - 5 }$ j/m $3$
D) $8.5 \times 10 ^ { - 6 }$ j/m $3$

Question

Quizplus · Accepted Answer

The energy density $ u $ in a dielectric is given by $ u = \frac{1}{2} \epsilon E^2 $, where $ \epsilon = \epsilon_0 K $. Substituting $ \epsilon_0 = 8.85 \times 10^{-12} \, \text{F/m} $, $ K = 2.3 $, and $ E = 1300 \, \text{N/C} $, we find $ u = 1.7 \times 10^{-5} \, \text{J/m}^3 $.

A 1300-N/C Electric Field in a Polyethylene Dielectric K=2.3K = 2.3K=2.3

A 1300-N/C Electric Field in a Polyethylene Dielectric $K = 2.3$