Which one of the following statement is `WRONG` in the context of X- rays generated from X- rays tube ?

Options

A. Wavelength of characteristic X - rays decreases when the atomic number of the target increases
B. Cut - off wavelength of the continuous X - rays depends on the atomic number of the target
C. Intensity on the electrical power given to the X - ray tube
D. Cut - off wavelength of the continuous X - rays depends on the energy of the electrons in X - ray tube

Answer

To solve the question regarding which statement is wrong in the context of X-rays generated from an X-ray tube, we will analyze each statement provided in the options.

### Step-by-Step Solution:

1. **Understanding the Basics of X-ray Generation**:
- X-rays are produced in an X-ray tube when high-energy electrons collide with a metal target. The energy of the electrons is converted into X-ray photons.

2. **Analyzing the Wavelength of Characteristic X-rays**:
- The relationship between energy (E), wavelength (λ), Planck's constant (h), and the speed of light (c) is given by the equation:
\[ E = \frac{hc}{\lambda} \]
- Rearranging this gives:
\[ \lambda = \frac{hc}{E} \]
- If we consider the energy of the electrons (E) to be related to the potential difference (V) applied in the X-ray tube, we can express it as:
\[ E = eV \]
- Substituting this into the wavelength equation gives:
\[ \lambda = \frac{hc}{eV} \]
- This shows that as the potential difference (V) increases, the wavelength (λ) decreases.

3. **Evaluating the Statements**:
- **Statement A**: "Wavelength of the characteristic X-ray decreases when atomic number of the target decreases."
- This statement is **correct**. Higher atomic number materials produce shorter wavelength X-rays.

- **Statement B**: "Cutoff wavelength of the continuous X-rays depend upon the atomic number."
- This statement is **wrong**. The cutoff wavelength depends primarily on the energy of the electrons, which is determined by the voltage, not directly on the atomic number.

- **Statement C**: "Intensity of the given power to the X-ray tube."
- This statement is incomplete but generally refers to the power input and its effect on intensity, which is a valid consideration.

- **Statement D**: "The cutoff wavelength of the continuous X-rays depend upon the energy of the electron."
- This statement is **correct**. The cutoff wavelength is indeed related to the energy of the electrons.

4. **Conclusion**:
- The statement that is wrong in the context of X-rays generated from an X-ray tube is **Statement B**.

### Final Answer:
- The wrong statement is **B**: "Cutoff wavelength of the continuous X-rays depend upon the atomic number."