Lasers have been used to suspend spherical glass beads in the Earth's gravitational field. a) A black bead has a mass of 1 micrograms and a density of 0.200 g/cm^3. Determine the radiation intensity needed to support the bead. b) If the beam has a radius of 0.200 cm, what is the power required for this laser.(adsbygoogle = window.adsbygoogle || []).push({});

I know that density = mass/volume, so I can get the volume from the density and mass. I know that the energy density = energy/volume. Also, I know that intensity = speed of light*energy density. How do I get the energy or am I doing this wrong? Please help...any help would be great! thx! :)

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# Homework Help: Problem with electromagnetic waves

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