What Atomic Transition Occurs in the Atoms of Hydrogen Gas

question 448

Multiple Choice

What atomic transition occurs in the atoms of hydrogen gas in the spiral arms of the Milky Way Galaxy to produce the 21-cm radio emission?

• A) transition from n = 2 level to n = 1 level in atomic hydrogen
• B) change in rotation of the molecule H₂ about an axis perpendicular to the molecular axis
• C) change in the vibrational state of the H atoms in the H₂ molecule
• D) inversion of the electron spin relative to the proton spin, from parallel to antiparallel

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Definitions:

Kinesthesia

The sense that detects bodily position, weight, or movement of the muscles, tendons, and joints, enabling physical coordination.

Sensory Interaction

The process by which multiple sensory systems combine to influence perception and behavior.

Psychokinesis

The supposed ability to move or manipulate objects with the mind without physical interaction.

Dissociation

A psychological process where a person disconnects from their thoughts, feelings, memories or sense of identity.