Which of the following statements is incorrect ?

Options

A. Particle nature of radiations can be experimentally demonstrated by Compton effect
B. Wave nature of electrons can be experimentally domonstrated by diffraction experiment
C. The value of Planck's constant, h is `6.62 xx 10^(-34) Js`.
D. Intensity of light is directly proportional to its frequency.

Answer

To determine which of the following statements is incorrect, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A: Particle nature of radiations can be experimentally demonstrated by Compton effect.**
- The Compton effect indeed demonstrates the particle nature of light, showing that photons (particles of light) can collide with electrons, resulting in a change in the wavelength of the light. Therefore, this statement is **correct**.

2. **Statement B: Diffraction explains wave nature.**
- Diffraction is a phenomenon that occurs when waves encounter an obstacle or a slit that is comparable in size to their wavelength. This behavior is characteristic of waves. Hence, this statement is **correct**.

3. **Statement C: The value of Planck's constant (h) is 6.626 x 10^-34 joules second.**
- Planck's constant is indeed a fundamental constant in quantum mechanics, and its value is accurately stated as 6.626 x 10^-34 Js. Therefore, this statement is **correct**.

4. **Statement D: The intensity of light directly depends upon the frequency.**
- The intensity of light is related to the amplitude of the wave rather than its frequency. While frequency affects the energy of the photons, intensity is more about the number of photons hitting a surface per unit time. Thus, this statement is **incorrect**.

### Conclusion:
After analyzing all the statements, we find that **Statement D** is incorrect. Therefore, the answer to the question is that the incorrect statement is **Statement D**.

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