Question

The vector $\overrightarrow{H}$ in the far field of an antenna satisfies

• A. $▽\cdot \overrightarrow{H}=0and▽\times \overrightarrow{H}=0$
• B. $▽\cdot \overrightarrow{H}\ne 0and▽\times \overrightarrow{H}\ne 0$
• C. $▽\cdot \overrightarrow{H}\ne 0and▽\times \overrightarrow{H}=0$
• D. $▽\cdot \overrightarrow{H}=0and▽\times \overrightarrow{H}\ne 0$

Answer 1

The correct option is D $▽\cdot \overrightarrow{H}=0and▽\times \overrightarrow{H}\ne 0$

Ans : (c)

For field free space conditions have $J_c=0$

$▽\times \overrightarrow{H}=J_C+J_D$

$▽\times \overrightarrow{H}=J_C$

$▽\cdot \overrightarrow{H}=0$

So, $▽\times \overrightarrow{H}\ne 0and▽\cdot \overrightarrow{H}=0$