An electromagnetic wave propagates along the +y direction as shown in the figure.If the electric field at the origin is along the +z direction,what is the direction of the magnetic field?
A) +z
B) -z
C) +y
D) +x
E) -x

Question

An electromagnetic wave propagates along the +y direction as shown in the figure.If the electric field at the origin is along the +z direction,what is the direction of the magnetic field? 
A) +z 
B) -z 
C) +y 
D) +x 
E) -x

Quizplus · Accepted Answer

The direction of the magnetic field in an electromagnetic wave is perpendicular to both the direction of propagation and the electric field. In this case, since the electric field is along the +z direction and the wave is propagating along the +y direction, the magnetic field must be in the +x direction to satisfy the perpendicularity condition. Therefore, the correct choice is D) +x.

An Electromagnetic Wave Propagates Along the +Y Direction as Shown