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JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The energy density associated with electric field \(\overrightarrow{ E }\) and magnetic field \(B\) of an electromagnetic wave in free space is given by ( \(\epsilon_0-\) permittivity of free space, \(\mu_0\) - permeability of free space)
- A \(U _{ E }=\frac{ E ^2}{2 \epsilon_0}, U _{ B }=\frac{ B ^2}{2 \mu_0}\)
- B \(U _{ E }=\frac{ E ^2}{2 \epsilon_0}, U _{ B }=\frac{\mu_0 B ^2}{2}\)
- C \(U _{ E }=\frac{\epsilon_0 E ^2}{2}, U _{ B }=\frac{\mu_0 B ^2}{2}\)
- D \(U _{ E }=\frac{\epsilon_0 E ^2}{2}, U _{ B }=\frac{ B ^2}{2 \mu_0}\)
Answer & Solution
Correct Answer
(D) \(U _{ E }=\frac{\epsilon_0 E ^2}{2}, U _{ B }=\frac{ B ^2}{2 \mu_0}\)
Step-by-step Solution
Detailed explanation
\(U _{ E }=\frac{1}{2} \epsilon_0 E ^2, U _{ B }=\frac{ B ^2}{2 \mu_0}\)
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