- A$\text{h}$
- B$\frac{\text{h}}{2}$
- C$\frac{\text{h}}{2\pi}$
- D$\frac{\text{h}}{\lambda}$
Explanation:
According to Bohr's atomic theory, the orbital angular momentum of an electron is an integral multiplt of $\frac{\text{h}}{2\pi}$
$\therefore\ \text{L}_\text{n}=\frac{\text{nh}}{2\pi}$
Here,
n = Principal quantum number
The minimum of n is 1
Thus, the minimum value of the orbit angular momentum of the electron in a hydrogen is given by $\text{L}=\frac{\text{h}}{2\pi}$
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Assertion : A compass needle when placed on the magnetic north pole of the earth rotates in vertical direction.
Reason : The earth has only horizontal component of its magnetic field at the north poles.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
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(c) 70% |
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(a) 6000 Å |
(b) 5000 Å |
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