(a) What is the intensity in W/m2 of a laser beam used to burn away cancerous tissue that, when 90.0% absorbed, puts 500 J of energy into a circular spot 2.00 mm in diameter in 4.00 s?(b) Discuss how this intensity compares to the average intensity of sunlight (about 700 W/m2 ) and the implications that would have if the laser beam entered your eye. Note how your answer depends on the time duration ofthe exposure.

(a) What is the intensity in W/m2 of a laser beam used to burn away cancerous tissue that, when 90.0% absorbed, puts 500 J of energy into a circular spot 2.00 mm in diameter in 4.00 s?(b) Discuss how this intensity compares to the average intensity of sunlight (about 700 W/m2 ) and the implications that would have if the laser beam entered your eye. Note how your answer depends on the time duration ofthe exposure.

Astronomy

1st Edition

ISBN:9781938168284

Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Publisher:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Chapter5: Radiation And Spectra

Section: Chapter Questions

Problem 3E: Is your textbook the kind of idealized object (described in section on radiation laws) that absorbs...

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