The magnetic field in a plane electromagnetic wave is given by ${\mathrm{B}}_{\mathrm{y}}=2\times {10}^{-7}\sin (0.5\times {10}^{3}x+1.5\times {10}^{11}t)$ Write an expression for the electric field.

$E_0=B_{0}c=2\times {10}^{-7}T\times 3\times {10}^{8}m/s=$$6\times {10}^{1}V/m$

The electric field component is perpendicular to the direction of propagation and the direction of magnetic field. Therefore, the electric field component along the z-axis is obtained as 

$E_z=60\sin \left(0.5\times {10}^{3}x+1.5\times {10}^{11}t\right)V/m$