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# The electric field intensity produced by the radiation coming from $100\;w$ bulls at a $3\;m$ distance is E. The electric field intensity produced by the radiation coming from 50 w bulb at the same distance is :

$\begin{array}{1 1} E/2 \\ 2E \\ E \sqrt 2 \\ \sqrt 2 E \end{array}$

$E= \large\frac{w}{At}$
$\quad= \large\frac{P}{A}$
But $\large\frac{w}{t}$$=P$
$\therefore E \alpha P$
Hence $\large\frac{E^1}{E^2} =\frac{P^1}{P}$
$\qquad= \large\frac{50}{100}$
$\qquad= \large\frac{1}{2}$
$E^1= \large\frac{E}{2}$