Question

An electromagnetic wave is transporting energy in the negative y direction. At one point and one instant the magnetic field is in the positive x direction. The electric field at that point and instant is:Why is (D) the answer? I thought it's (C)A) positive y directionB) negative y directionC) positive z directionD) negative z direction

Answer 1

Answer:negative Z direction

Step-by-step explanation:

It is given that EM wave is travelling in negative y direction i.e. -
`\hat{j}`

Magnetic Field is in positive x direction i.e.
`\hat{i}`

We know that Electric field and magnetic field are perpendicular to each other and they are mutually perpendicular to direction of wave propagation.

Mathematically if Electric field is in negative z direction it will yield the direction of wave propagation

`=(-\hat{k})* \hat{i}`

`=-\hat{j}`