He-Ne (Helium-Neon) lasers are often used in physics demonstrations. Mine is labelled as about 5 mW and 650 nm. Let's approximate that the light is spread over a cylindrical beam about 1 mm in diameter. a. What's the intensity of the beam (approximately)? b. What are the maximum electric and magnetic field values? What are the average values? Explain briefly why those are different. c. What's the average energy density of the beam? d. What's the frequency of the EM wave?

He-Ne (Helium-Neon) lasers are often used in physics demonstrations. Mine is labelled as about 5 mW and 650 nm. Let's approximate that the light is spread over a cylindrical beam about 1 mm in diameter. a. What's the intensity of the beam (approximately)? b. What are the maximum electric and magnetic field values? What are the average values? Explain briefly why those are different. c. What's the average energy density of the beam? d. What's the frequency of the EM wave?

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter16: Waves

Section: Chapter Questions

Problem 134AP: (a) What is the intensity of a laser beam used to burn away cancerous tissue that, when 90.0%...

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