The H _- line has a wavelength of 434.0 nm when observed in the laboratory.If the H _- line appears in a stars spectrum at 434.5 nm,what is the radial velocity of the star? A) 346 km/sec away from the observer B) 346 km/sec toward the observer C) 1.3*10⁸ m/sec away from the observer D) 1.3*10⁸ m/sec toward the observer E) The radial velocity of the star can not be determined from this information.

Question

Quizplus · Accepted Answer

The observed wavelength is longer than the laboratory wavelength, indicating a redshift. This means the star is moving away from the observer. The radial velocity can be calculated using the formula: v = c * (λ_observed - λ_rest) / λ_rest, where c is the speed of light. Plugging in the values gives approximately 346 km/sec away from the observer.

The H - Line Has a Wavelength of 434

The H _- Line Has a Wavelength of 434