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The electric field a plane electromagnetic wave is given by : E_y = 69 sin [0.6 × 10^3 x - 1.8 × 10^11 t] V/m. The expression for magnetic field associated with this electromagnetic wave is ____ T.

1. B_z = 2.3 × 10^-7 sin [0.6 × 10^3 x - 1.8 × 10^11 t]
2. B_z = 2.3 × 10^-7 sin [0.6 × 10^3 x + 1.8 × 10^11 t]
3. B_y = 69 sin [0.6 × 10^3 x + 1.8 × 10^11 t]
4. B_y = 2.3 × 10^-7 sin [0.6 × 10^3 x - 1.8 × 10^11 t]

Correct answer: B_z = 2.3 × 10^-7 sin [0.6 × 10^3 x - 1.8 × 10^11 t]

Solution

The correct option represents the magnetic field associated with the given electric field of an electromagnetic wave, following the relationship between electric and magnetic fields in a plane wave, where the magnetic field is perpendicular to the electric field and has a specific amplitude determined by the speed of light.

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