The electric field in an electromagnetic wave is given by E = 56.5 sin ω(t - x/c)Nc-1. Find the intensity of the wave if it is propagating along x-axis in the free space. - Physics (JEE Main)

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MCQ

The electric field in an electromagnetic wave is given by E = 56.5 sin ω(t - x/c)Nc-1. Find the intensity of the wave if it is propagating along x-axis in the free space.

(Given ε0 = 8.85 × 10-12 C2 N-1 m-2)

Options

  • 5.65 Wm-2

  • 4.24 Wm-2

  • 1.9 × 10-7 Wm-2

  •  56.5 Wm-2

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Solution

4.24 Wm-2

Explanation:

Intensity of EM wave is given by

I = `1/2` ∈0 E2 C

= `1/2xx8.85xx10^-12xx(56.5)^2xx3xx10^8`

= 4.24 Wm-2

  Is there an error in this question or solution?

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