A plane electromagnetic wave, has frequency of 2.0 × 10¹⁰ Hz and its energy density is 1.02 × 10⁻⁸ J/m³ in vacuum. The amplitude of the magnetic field of the wave is close to (1/(4πε₀) = 9 × 10⁹ Nm²/C² and speed of light = 3 × 10⁸ ms⁻¹):
A plane electromagnetic wave, has frequency of 2.0 × 10¹⁰ Hz and its energy density is 1.02 × 10⁻⁸ J/m³ in vacuum. The amplitude of the magnetic field of the wave is close to (1/(4πε₀) = 9 × 10⁹ Nm²/C² and speed of light = 3 × 10⁸ ms⁻¹):
Option 1 -
150nT
Option 2 -
180nT
Option 3 -
190nT
Option 4 -
160nT
Asked by Shiksha User
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1 Answer
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Correct Option - 4
Detailed Solution:Energy Density = 1/2 B²/µ?
B = √ (2 × µ? × Energy density)
B = √ (2 × 4π × 10? × 1.02 × 10? ) = 160 × 10? = 160nT
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