8.5 A small sphere with radius R and density p shall be hold in suspense against the gravitational force using the radiation pressure of a vertically aligned laser beam (see Figure 1). Calculate the required intensity of the laser that is assumed to be constant over the cross section of the sphere. Assume the sphere having a reflectivity of 100%. 2R m. g Figure 1: Sphere of radius R and density p levitates in the gravitational field due to a laser beam (red lines).

8.5 A small sphere with radius R and density p shall be hold in suspense against the gravitational force using the radiation pressure of a vertically aligned laser beam (see Figure 1). Calculate the required intensity of the laser that is assumed to be constant over the cross section of the sphere. Assume the sphere having a reflectivity of 100%. 2R m. g Figure 1: Sphere of radius R and density p levitates in the gravitational field due to a laser beam (red lines).

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter34: Maxwell’s Equations And Electromagnetic Waves

Section: Chapter Questions

Problem 60PQ

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