4. Darcy installed a motion-activated outdoor light so that it would light a path to
the door on her deck. If you know AB = 10 feet, and BE and BD trisect 2ABC, what
is the perimeter of the deck area to the right of the beam of light (ABDC)?
Answer:In the path of a uniform light beam of large cross-sectional area and intensity I. a solid sphere of redius R which is perfectly reflecting is placed . Find the force exerted on this sphere due to the light beam.
