When a surface is irradiated with light of wavelength

PHYSICS · Single correct · CBSE · Physics · Dual Nature of Radiation and Matter · Dual Nature of Radiation and Matter

Problem

4950\text{ \AA}

, a photocurrent appears that vanishes if a retarding potential greater than

0.6\text{ V}

is applied across the phototube. When a second source of light is used, the critical retarding potential is

1.1\text{ V}

. The work function of the emitting surface is (1)

2.2\text{ eV}

(2)

1.5\text{ eV}

(3)

1.9\text{ eV}

(4)

1.1\text{ eV}