NEET Physics Question - Modern Physics

Assertion (A): When white radiations (visible light) are passed through a sample of hydrogen gas at room temperature, absorption lines corresponding to Lyman series only are obtained.

Reason (R): At room temperature hydrogen atom is in the ground state.

Both (A) & (R) are true and the (R) is the correct explanation of the (A)

Both (A) & (R) are true but the (R) is not the correct explanation of the (A)

(A) is true but (R) is false

Both (A) and (R) are false

Solution:

At room temperature, hydrogen atoms are almost exclusively in their ground state (n=1). Therefore, absorption can only occur from \(n=1\) to higher energy levels (Lyman series). If 'white radiations' are assumed to include the necessary UV components, then only Lyman series absorption lines would appear, as other series require excited initial states.

Rankers Physics

Hydrogen Absorption Spectrum at Room Temperature

Solution:

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