Photon Wavelength & Energy – Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

Assertion (A): The smaller the wavelength of a photon, the more energy it has. Reason (R): The smaller the wavelength of a photon, the less momentum it has.  
(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 true: Energy \(E = hc/\lambda\), so smaller \(\lambda\) means more energy. Reason (R) is false: Momentum \(p = h/\lambda\), so smaller \(\lambda\) means more momentum. (A) is true, (R) is false.

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