Question 201: Dual Nature of Matter and Radiation

Question

When a certain photosensitive surface is illuminated with monochromatic light of frequency v, the stopping
potential for the current is –V0/2. When the surface is illuminated by monochromatic light of frequency v/2, the stopping potential is – V0. The threshold frequency for photoelectric emission is :

Accepted Answer

EinsteinÃ¢ÂÂs photoelectric equation in the two cases
is given by
$${{e{V_0}} \over {\Delta E}} = h\upsilon  - h{\upsilon _0}$$ ......(i)
and $$e{V_0} = {{h\upsilon } \over 2} - h{\upsilon _0}$$ .....(ii)
From eqn. (i) and (ii),
$${1 \over 2} = {{h\upsilon  - h{\upsilon _0}} \over {{{h\upsilon } \over 2} - h{\upsilon _0}}}$$
$$ \Rightarrow $$ $${\upsilon _0} = {3 \over 2}\upsilon $$

Answer

2$$v$$

Answer

$${4 \over 3}v$$

Answer

$${{3v} \over 2}$$

Answer

$${{5v} \over 3}$$

Dual Nature of Matter and Radiation

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