Question $29$

$3\mathrm{.}3$ pts

If we halve the distance from an isotropic source of EM waves, the electric field amplitude will be

$\frac{1}{2}$ of its initial value.

$\frac{1}{4}$ of its initial value.

$\sqrt[\phantom{2}]{2}$ of its initial value.

$\frac{1}{\sqrt[\phantom{2}]{2}}$ of its initial value.

$2$ times its initial value.