The angular momentum for the electron in Bohr’s orbit is L. If the electron is assumed to revolve in second orbit of hydrogen atom, then the change in angular momentum will be
Show Hint
In Bohr’s model, angular momentum is quantized: Ln = nh. The change in an gular momentum between orbits is simply the difference in their quantized values.
- L
- 1L
- 2L
- 1.5L
The Correct Option is A
Solution and Explanation
Step 1: Formula for Angular Momentum
The angular momentum is given by:
\( L = \frac{nh}{2\pi} \)
Where:
- \( n \): Principal quantum number
- \( h \): Planck's constant
Step 2: Calculate \( L_1 \) for \( n = 1 \)
Substitute \( n = 1 \):
\[ L_1 = \frac{1 \cdot h}{2\pi} = L \]
Step 3: Calculate \( L_2 \) for \( n = 2 \)
Substitute \( n = 2 \):
\[ L_2 = \frac{2 \cdot h}{2\pi} = 2L \]
Step 4: Calculate Change in Angular Momentum (\( \Delta L \))
The change in angular momentum is:
\[ \Delta L = L_2 - L_1 = 2L - L = L \]
Conclusion:
The change in angular momentum is \( \Delta L = L. \)
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