A Blue Line in the Spectrum of the Hydrogen Atom

question 97

Multiple Choice

A blue line in the spectrum of the hydrogen atom has a wavelength  = 486 nm. In the hydrogen-atom spectrum emitted by a distant galaxy, this line is observed on Earth at  = 550 nm. With what speed is this galaxy receding from us? The speed of light is 3.0  10⁸ m/s.)

• A) 1.31  10⁷ m/s
• B) 1.13  10⁸ m/s
• C) 2.65  10⁸ m/s
• D) 3.49  10⁷ m/s
• E) 3.95  10⁷ m/s

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Definitions:

Pleasant Event

An occurrence or experience that brings joy, satisfaction, or happiness to those involved.

Negative Reinforcement

A psychological strategy that involves the removal of an unfavorable outcome or stimulus to increase the likelihood of a desired behavior.

Positive Reinforcement

A technique in behavior management that involves providing a reward or incentive following a desired behavior to increase the likelihood of its recurrence.

Unpleasant Event

Refers to an occurrence that is disagreeable or causes discomfort.