The fig. shows the variation of photon current with anode potential for a photo-sensitive surface for three different radiation. Let `I_(a), I_(b) and I_(c)` be the intensities and `f_(a), f_(b) and f_(c)` be the frequency for the curves a,b and c respectively.

Options

A. `f_(a) = f_(b)` and `I_(a) ne I_(b)`
B. `f_(a) = f_(c)` and `I_(a) = I_(c)`
C. `f_(a) = f_(b)` and `I_(a) = I_(b)`
D. `f_(b) = f_(c)` and `I_(b) = I_(c)`

Answer

A

Explanation

Saturation current proportional to intensity while stopping potential increases with increase in frequency. Hence, `f_(e)=f_(b)` while `l_(1) lt l_(b)`