Question Analysis: Assertion (A) and Reason (R) based on Photoelectric Effect.

Step 1 (Governing Law & Data): [1/3 Mark]

The photoelectric effect occurs only if the energy of the incident photon ($E = h\nu = \frac{hc}{\lambda}$) is greater than or equal to the work function ($\Phi_0$) of the metal surface. For Zinc, the work function is approximately $\Phi_0 \approx 4.3 \text{ eV}$.

Step 2 (Mathematical Working): [1/3 Mark]

• The wavelength of yellow light ($\lambda_{yellow}$) ranges approximately from $570 \text{ nm}$ to $590 \text{ nm}$.
• Calculating the energy of a yellow light photon: $$E = \frac{hc}{\lambda} \approx \frac{1240 \text{ eV}\cdot\text{nm}}{580 \text{ nm}} \approx 2.14 \text{ eV}$$
• Comparing the values: $$2.14 \text{ eV} < 4.3 \text{ eV} \implies E < \Phi_0$$

Step 3 (Final Concluded Answer): [1/3 Mark]

Since the energy of the yellow light photon is less than the work function of zinc, no photoelectrons will be ejected. Therefore, Assertion (A) is False and Reason (R) is False.

💡 EL10 Concept Insight: Think of the work function like the "entry fee" to leave the metal; yellow light is like a person who doesn't have enough money to pay that fee, so they simply can't get out, no matter how many of them show up.