Statement-1 : In photoelectric effect, the number of photoelectrons emitted is always equal to number of photons incident.
and
Statement-2 : All the photons fallin on the surface will eject photoelctron, is not necessary.

Options

A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-10
B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-10
C. Statement-1 is True, Statement-2 is False.
D. Statement-1 is False, Statement-2 is True.

Answer

To solve the question regarding the statements about the photoelectric effect, let's analyze each statement step by step.

### Step 1: Analyze Statement 1
**Statement 1:** In the photoelectric effect, the number of photoelectrons emitted is always equal to the number of photons incident.

**Explanation:**
- The photoelectric effect states that when light (photons) hits a metal surface, it can eject electrons (photoelectrons) if the energy of the photons is above a certain threshold (the work function of the metal).
- However, not every photon will necessarily cause the emission of a photoelectron. Only those photons with energy greater than the work function will eject electrons. Therefore, the number of emitted photoelectrons can be less than the number of incident photons.

**Conclusion for Statement 1:** This statement is **false**.

### Step 2: Analyze Statement 2
**Statement 2:** All the photons falling on the surface will eject photoelectrons, is not necessary.

**Explanation:**
- This statement correctly reflects the nature of the photoelectric effect. Not all photons will have enough energy to overcome the work function of the metal. Only those photons with energy greater than the threshold energy will eject photoelectrons.
- Therefore, it is indeed not necessary that all incident photons will lead to the emission of photoelectrons.

**Conclusion for Statement 2:** This statement is **true**.

### Step 3: Determine the Relationship Between the Statements
Now we need to check if Statement 2 provides a correct explanation for Statement 1.

- Since Statement 1 is false (the number of emitted photoelectrons is not always equal to the number of incident photons), Statement 2 cannot be considered a correct explanation for Statement 1.

### Final Conclusion
- **Statement 1:** False
- **Statement 2:** True
- Statement 2 does not explain Statement 1.

Thus, the correct answer is that Statement 1 is false and Statement 2 is true.