Need help with this question ### Understanding Hydrogen Emission and Relative Velocity1. **Hydrogen Excitation and Emission**: - When hydrogen is energized by a strong electric field or ultraviolet light, it fluoresces, similar to the way ceiling lights illuminate interiors. - Unlike an incandescent bulb, the light emitted is not continuous; it consists of specific emission lines related to the element. - The longest visible wavelength for hydrogen is the red hydrogen-alpha line at 656.28 nm.2. **Astronomical Observation**: - Considering an observation of the Orion Nebula, a massive hydrogen gas cloud located 1300 light years from Earth. - An astronomer observes that the hydrogen-alpha emission is shifted to 656.18 nm, suggesting relative motion between the gas cloud and Earth.3. **Problem**: - A) Determine the relative velocity (in km/s) between Earth and the Orion Nebula.This text and problem are designed to help students explore concepts related to spectroscopy and the Doppler effect, commonly used in astronomy to measure the motion of celestial objects relative to Earth.

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1. When hydrogen is energized by a strong electric field or incident ultraviolet light, the gas fluoresces (much like the ceiling lights we use to illuminate the interior of buildings). The spectrum of excitation is not continuous like an incandescent light bulb though; instead, the light consists of discrete lines of emission at various wavelengths which are specific to the element emitting the light. The longest visible wavelength for hydrogen is a red line known as the hydrogen-alpha line, which has a wavelength of 656.28 nm. Suppose an astronomer observes the Orion Nebula (an enormous hydrogen gas cloud 1300 light years away) has a hydrogen-alpha emission with a shifted wavelength of 656.18 nm, which implies relative motion between the gas cloud and Earth.

1. When hydrogen is energized by a strong electric field or incident ultraviolet light, the gas fluoresces (much like the ceiling lights we use to illuminate the interior of buildings). The spectrum of excitation is not continuous like an incandescent light bulb though; instead, the light consists of discrete lines of emission at various wavelengths which are specific to the element emitting the light. The longest visible wavelength for hydrogen is a red line known as the hydrogen-alpha line, which has a wavelength of 656.28 nm. Suppose an astronomer observes the Orion Nebula (an enormous hydrogen gas cloud 1300 light years away) has a hydrogen-alpha emission with a shifted wavelength of 656.18 nm, which implies relative motion between the gas cloud and Earth.