Photoelectric Emission KE – Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

Assertion (A): In the process of photo electric emission, all the emitted photoelectrons have same KE. Reason (R): According to Einstein's photo electric equation \(KE= h\nu - \phi\).  
(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(3) (A) is true but (R) is false
(4) 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:

Assertion (A) is false: Kinetic energy of emitted photoelectrons varies from zero to maximum. Reason (R) is false: Einstein's equation is \(KE_{max}= h\nu - \phi\). Both statements are false.

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