CBSE Class 12 · 2011 · All India · Modern PhysicsShort Answer

Define the term 'stopping potential' in relation to the photoelectric effect.

Answer: Retarding potential at which photocurrent becomes zero; $e V_{0} = K_{ma x}$ .

Solution

Stopping potential

V_{0}

is the minimum retarding (negative) potential applied to the collecting plate at which the photoelectric current just becomes zero.
At this potential even the most energetic photoelectrons are turned back, so

e V_{0} = K_{ma x} .

Its value depends on the frequency of the incident light (not on its intensity).

e V_{0} = K_{ma x}

CBSE Class 12 Board · 2011 · All India · Subjective

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