The cathode of a photocell is changed such that the work function… - Vidyadip

MCQ

The cathode of a photocell is changed such that the work function changes from $w_1$ to $w_2\left(w_2 > w_1\right)$. If the saturation currents before and after the change are $l_1$ and $l_2$ and all other conditions are unchanged, then (assuming $h v > w_2$ )

✓
$I_1=I_2$
B
$I_1 < I_2$
C
$I_1 > I_2$
D
$I_1 < I_2 < 2I_2$

✓

Answer

Correct option: A.

$I_1=I_2$

a
(a)

Saturation current depends on intensity which does not change. Hence, $I_1=I_2$

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