COMEDK · Physics · 24. Electromagnetic Waves
A plane electromagnetic wave of frequency \(20 \mathrm{~MHz}\) travels through a space along \(x\)-direction. If the electric field vector at a certain point in space is \(6 \mathrm{~Vm}^{-1}\), then what is the magnetic field vector at that point?
- A \(2 \mathrm{~T}\)
- B \(2 \times 10^{-8} \mathrm{~T}\)
- C \(\dfrac{1}{2} \times 10^{-8} \mathrm{~T}\)
- D \(\dfrac{1}{2} \mathrm{~T}\)
Answer & Solution
Correct Answer
(B) \(2 \times 10^{-8} \mathrm{~T}\)
Step-by-step Solution
Detailed explanation
The relationship between the magnitude of the electric field \(E\) and the magnetic field \(B\) in an electromagnetic wave is given by \(E = cB\), where \(c\) is the speed of light in vacuum. Given \(E = 6 \mathrm{~Vm}^{-1}\) and \(c = 3 \times 10^8 \mathrm{~ms}^{-1}\). The…
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