Question: Choose the correct statement regarding the dual nature of matter and radiation.
Step 1 (Governing Law & Theoretical Basis): [0.5 Mark]
According to the de Broglie hypothesis and the principles of quantum mechanics, both electromagnetic radiation (photons) and subatomic particles (electrons) exhibit wave-particle duality. The momentum of a photon is given by:
$$p = \frac{h}{\lambda} = \frac{E}{c}$$The wavelength associated with a moving particle (matter wave) is given by:
$$\lambda = \frac{h}{p}$$Where $h$ is Planck's constant, $p$ is momentum, and $\lambda$ is the de Broglie wavelength.
Step 2 (Analysis of Statements): [0.25 Mark]
- (A) Incorrect: Electrons exhibit diffraction (e.g., Davisson-Germer experiment) just as photons do.
- (B) Incorrect: Photons possess momentum $p = \frac{h}{\lambda}$, which is why they exert radiation pressure.
- (C) Correct: Both photons (exhibiting photoelectric effect and interference) and electrons (exhibiting diffraction and particle-like collisions) demonstrate dual nature.
- (D) Incorrect: By definition, all electromagnetic radiations are quantized into photons.
Step 3 (Final Concluded Answer): [0.25 Mark]
The correct statement is (C) Photons of light and electrons both exhibit dual nature.
💡 EL10 Concept Insight: Think of it like this: just as a person can be both a "student" and a "child" depending on the situation, tiny things like light and electrons act like little solid balls (particles) when they hit something, but like rippling water (waves) when they travel through space.