Question

The equation of the corresponding electric field should be ?

Answer 1

Magnetic field of an electromagnetic wave is B = 12 × 10^-19 sin(kx - ωt) k T.

To find : The equation of corresponding electric field should be .....

solution : magnitude of electric field, E₀ = B₀c

where B₀ is the peak value of magnetic field and c is speed of light.

here B₀ = 12 × 10^-9 T , c = 3 × 10^8 m/s

so E₀ = 12 × 10^-9 × 3 × 10^8 = 3.6 N/C

as light is propagating in X direction

[ see equation of magnetic field, here phase constant (kx - ωt) shows light travels in magnetic field ]

but (E × B) || c ( velocity of light )

here B = k , c = i

then, E must be along j

Therefore the equation of electric field, E = 3.6 sin( kx - ωt) j N/C