1. (a) What is the intensity in W/m² of a laser beam used to burn away cancerous tissue that, when 90.0% absorbed, puts 650 J of energy into a circular spot 1.9 mm in diameter in 4 s? Hint: The laser is a collimated beam of light and does not produce a spherical wave. W/m² (b) Reflect on how this intensity compares to the average intensity of sunlight (about 1W/m²) and the implications that would have if the laser beam entered your eye. Note how your answer depends on the time duration of the exposure. The intensity of a laser is about be very damaging if they enter your eye. ✓times that of the sun, so clearly lasers can

1. (a) What is the intensity in W/m² of a laser beam used to burn away cancerous tissue that, when 90.0% absorbed, puts 650 J of energy into a circular spot 1.9 mm in diameter in 4 s? Hint: The laser is a collimated beam of light and does not produce a spherical wave. W/m² (b) Reflect on how this intensity compares to the average intensity of sunlight (about 1W/m²) and the implications that would have if the laser beam entered your eye. Note how your answer depends on the time duration of the exposure. The intensity of a laser is about be very damaging if they enter your eye. ✓times that of the sun, so clearly lasers can

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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