physics

A lamp is moved from 26 cm to 90 cm above the pages of a book. Compare the illumination on the book before and after the lamp is move.

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asked by marc
  1. The illumination varies as the inverse square of the distance..
    1/(26)^2
    1/(90)^2

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  2. .00148
    1.234e-4

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    posted by shrily

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