JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
In a plane electromagnetic wave, the directions of electric field and magnetic field are represented by \(\hat{ k }\) and \(2 \hat{ i }-2 \hat{ j },\) respectively What is the unit vector along direction of propagation of the wave.
- A \(\frac{1}{\sqrt{2}}(\hat{ i }+\hat{j})\)
- B \(\frac{1}{\sqrt{5}}(\hat{ i }+2 \hat{ j })\)
- C \(\frac{1}{\sqrt{5}}(2 \hat{ i }+\hat{ j })\)
- D \(\frac{1}{\sqrt{2}}(\hat{j}+\hat{k})\)
Answer & Solution
Correct Answer
(A) \(\frac{1}{\sqrt{2}}(\hat{ i }+\hat{j})\)
Step-by-step Solution
Detailed explanation
\(\hat{ E }=\hat{ k }\) \(\overrightarrow{ B }=2 \hat{ i }-2 \hat{ j } \Rightarrow \hat{ B }=\frac{\overrightarrow{ B }}{| B |}=\frac{2 \hat{ i }-2 \hat{ j }}{2 \sqrt{2}}\) \(\Rightarrow \hat{ B }=\frac{1}{\sqrt{2}}(\hat{ i }-\hat{j})\) Direction of wave propagation…
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