In Moseley's law `sqrt(v)=a(z-b),` the volue of the screening constant for K-series and L-series of X-rays are respectively

Options

A. 1, 6.4
B. 1,4
C. 4,6
D. 2,4

Explanation

To solve the question regarding the screening constants for K-series and L-series of X-rays in Moseley's law, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Moseley's Law**:
Moseley's law is given by the equation:
\[ \sqrt{v} = a(Z - b) \]
where \( v \) is the frequency of the emitted X-rays, \( Z \) is the atomic number, \( a \) is a constant, and \( b \) is the screening constant.

2. **Identify K-series and L-series**:
- The K-series refers to transitions from the second energy level (n=2) to the first energy level (n=1).
- The L-series refers to transitions from the third energy level (n=3) to the second energy level (n=2).

3. **Determine the Screening Constants**:
- For the K-series, the screening constant \( b \) is typically found to be 1.
- For the L-series, the screening constant \( b \) is found to be approximately 6.4.

4. **Conclusion**:
Therefore, the values of the screening constant for K-series and L-series of X-rays are:
- K-series: \( b = 1 \)
- L-series: \( b = 6.4 \)

### Final Answer:
The screening constants for K-series and L-series of X-rays are 1 and 6.4, respectively.

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