Statement-1 : In a photoelectric effect experiment different photoelectron have different kinetic energy.
and
Statement-2 : In the incident radiation different photons must have different energy.

Options

A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-9
B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-9
C. Statement-1 is True, Statement-2 is False.
D. Statement-1 is False, Statement-2 is True.

Answer

To analyze the given statements regarding the photoelectric effect, let's break down the problem step by step.

### Step-by-Step Solution:

**Step 1: Analyze Statement-1**
- Statement-1 claims that in a photoelectric effect experiment, different photoelectrons have different kinetic energy.
- In the photoelectric effect, when light (photons) strikes a metal surface, electrons are emitted. The kinetic energy (KE) of these emitted electrons can be expressed as:
\[ KE = E_{photon} - \phi \]
where \(E_{photon}\) is the energy of the incident photon and \(\phi\) is the work function of the metal.
- Since the energy of the incident photons can vary (especially in polychromatic light), the emitted electrons can indeed have different kinetic energies. Thus, Statement-1 is **correct**.

**Step 2: Analyze Statement-2**
- Statement-2 states that in the incident radiation, different photons must have different energy.
- There are two types of radiation: monochromatic and polychromatic.
- **Monochromatic Radiation**: All photons have the same energy (e.g., light of a single wavelength).
- **Polychromatic Radiation**: Photons can have different energies (e.g., white light containing multiple wavelengths).
- The statement implies that it is necessary for different photons to have different energies, which is not always true. In monochromatic light, all photons have the same energy. Therefore, Statement-2 is **incorrect**.

**Step 3: Conclusion**
- Based on the analysis:
- Statement-1 is true.
- Statement-2 is false.
- Thus, the correct option is that the first statement is true and the second statement is false.

### Final Answer:
The correct option is: **Statement-1 is true and Statement-2 is false.**

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