JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
Electric field in a plane electromagnetic wave is given by \({E}=50 \sin \left(500 {x}-10 \times 10^{10} {t}\right) \,{V} / {m}\) The velocity of electromagnetic wave in this medium is : (Given \({C}=\) speed of light in vacuum)
- A \(\frac{3}{2} {C}\)
- B \(C\)
- C \(\frac{2}{3} C\)
- D \(\frac{{C}}{2}\)
Answer & Solution
Correct Answer
(C) \(\frac{2}{3} C\)
Step-by-step Solution
Detailed explanation
\({V}=\frac{\omega}{{K}}=\frac{10 \times 10^{10}}{500}=2 \times 10^{8}\) \(V=\frac{2 {C}}{3}\)
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