Problems 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.

Problems 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.

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter4: Diffraction

Section: Chapter Questions

Problem 102AP: Radio telescopes are telescopes used for the detection of radio emission from space. Because radio...

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