Kinetic Energy and Photoelectron Emission – Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

Assertion (A): Kinetic energy of photoelectrons emitted by a photosensitive surface depends upon the intensity of incident photon. Reason (R): The ejection of electrons from metallic surface is possible with frequency of incident photon below the threshold frequency.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Photoelectric Effects and deBroglie Equation. Understanding the underlying formula is key to arriving at the correct answer below:

Kinetic energy of photoelectrons depends on the frequency of incident light, not its intensity. Photoelectric emission requires the incident photon's frequency to be above the threshold frequency \(\nu_0\). Thus, both assertion (A) and reason (R) are false.

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