Home
Class 12
PHYSICS
According to Moseley's law, the ratio of...

According to Moseley's law, the ratio of the slope of graph between `sqrtf` and Z for `K_beta` and `K_alpha` is

A

`sqrt((32)/(27))`

B

`sqrt((27)/(32))`

C

`sqrt((33)/(22))`

D

`sqrt((22)/(33))`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem regarding Moseley's law and the ratio of the slope of the graph between \( \sqrt{f} \) and \( Z \) for \( K_{\beta} \) and \( K_{\alpha} \), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding Moseley's Law**: According to Moseley's law, the frequency \( f \) of the X-ray emitted by an atom can be expressed as: \[ f \propto (Z - 1)^2 \] where \( Z \) is the atomic number. 2. **Frequency Expressions for \( K_{\alpha} \) and \( K_{\beta} \)**: - For \( K_{\alpha} \) transition (where \( n = 2 \)): \[ f_{\alpha} = R \cdot (Z - 1)^2 \cdot \left( \frac{1}{1^2} - \frac{1}{2^2} \right) = R \cdot (Z - 1)^2 \cdot \left( 1 - \frac{1}{4} \right) = R \cdot (Z - 1)^2 \cdot \frac{3}{4} \] Thus, we can write: \[ \sqrt{f_{\alpha}} = \sqrt{R} \cdot (Z - 1) \cdot \sqrt{\frac{3}{4}} \] - For \( K_{\beta} \) transition (where \( n = 3 \)): \[ f_{\beta} = R \cdot (Z - 1)^2 \cdot \left( \frac{1}{1^2} - \frac{1}{3^2} \right) = R \cdot (Z - 1)^2 \cdot \left( 1 - \frac{1}{9} \right) = R \cdot (Z - 1)^2 \cdot \frac{8}{9} \] Thus, we can write: \[ \sqrt{f_{\beta}} = \sqrt{R} \cdot (Z - 1) \cdot \sqrt{\frac{8}{9}} \] 3. **Finding the Slopes**: - The slope of the graph of \( \sqrt{f} \) vs \( Z \) for \( K_{\alpha} \) is: \[ m_{\alpha} = \sqrt{R} \cdot \sqrt{\frac{3}{4}} \] - The slope of the graph of \( \sqrt{f} \) vs \( Z \) for \( K_{\beta} \) is: \[ m_{\beta} = \sqrt{R} \cdot \sqrt{\frac{8}{9}} \] 4. **Calculating the Ratio of Slopes**: - The ratio of the slopes \( \frac{m_{\beta}}{m_{\alpha}} \) is: \[ \frac{m_{\beta}}{m_{\alpha}} = \frac{\sqrt{R} \cdot \sqrt{\frac{8}{9}}}{\sqrt{R} \cdot \sqrt{\frac{3}{4}}} \] - Simplifying this gives: \[ = \frac{\sqrt{\frac{8}{9}}}{\sqrt{\frac{3}{4}}} = \frac{\sqrt{8} \cdot \sqrt{4}}{\sqrt{9} \cdot \sqrt{3}} = \frac{4\sqrt{2}}{3\sqrt{3}} = \frac{4\sqrt{2}}{3\sqrt{3}} \] 5. **Final Ratio**: - The final ratio of the slopes is: \[ \frac{m_{\beta}}{m_{\alpha}} = \frac{8}{9} \div \frac{3}{4} = \frac{8 \cdot 4}{9 \cdot 3} = \frac{32}{27} \] ### Conclusion: The ratio of the slope of the graph between \( \sqrt{f} \) and \( Z \) for \( K_{\beta} \) and \( K_{\alpha} \) is \( \frac{32}{27} \).

To solve the problem regarding Moseley's law and the ratio of the slope of the graph between \( \sqrt{f} \) and \( Z \) for \( K_{\beta} \) and \( K_{\alpha} \), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding Moseley's Law**: According to Moseley's law, the frequency \( f \) of the X-ray emitted by an atom can be expressed as: \[ f \propto (Z - 1)^2 \] ...
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ATOMIC PHYSICS

    RESONANCE ENGLISH|Exercise Exercise-2 part-II Single and double value integer type|12 Videos
  • ATOMIC PHYSICS

    RESONANCE ENGLISH|Exercise Exercise-2 part-III one or more than one options correct type|14 Videos
  • ATOMIC PHYSICS

    RESONANCE ENGLISH|Exercise Exercise ( Part II : Only one one correct type)|37 Videos
  • ALTERNATING CURRENT

    RESONANCE ENGLISH|Exercise HIGH LEVEL PROBLEMS|11 Videos
  • CAPACITANCE

    RESONANCE ENGLISH|Exercise High Level Problems|16 Videos

Similar Questions

Explore conceptually related problems

According to Moseley.s law, the frequency of a spectral line in X-ray spectrum varies as

According to moselay.s law, the frequency (vartheta) of the Kalpha line and the atomic number (z) of the element have the relation (A and B) are constants

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

In the experiment on photoelectric effect, the graph between E_K(max) and v is found to be a straight line as sshoen in fig. The threshold frequency and Planck's constant according to this graph are

The energy of a silver atom with a vacancy in K shell is 25.31 keV, in L shell is 3.56 keV and in M shell is 0.530 keV higher than the energy of the atom with no vacancy. Find the frequency of K_alpha , K_beta and L_alpha X-rays of silver.

In the Moseley relation, sqrt(v)=a(Z-b) which will have the greater value for the constant a for K_(alpha) or K_(beta) transition?

Moseley's law for characteristic X-rays is sqrt v = a(Z-b) . In this,

Use Moseley's law with b = 1 to find the frequency of the K_alpha X-ray of La(Z = 57) if the frequency of the K_alpha X-ray of Cu(Z = 29) is known to be 1*88 xx 10^(18) Hz.

Use Moseley's law with b = 1 to find the frequency of the K_alpha X-ray of La(Z = 57) if the frequency of the K_alpha X-ray of Cu(Z = 29) is known to be 1*88 xx 10^(18) Hz.

Use Moseley's law with b = 1 to find the frequency of the K_alpha X-ray of La(Z = 57) if the frequency of the K_alpha X-ray of Cu(Z = 29) is known to be 1*88 xx 10^(18) Hz.