4 ms·

inverse square law

• shagie 5y ago
  That applies to omnidirectional broadcast of power rather than beams.
  • beecafe 5y ago
    You can't make a perfectly straight beam due to imperfect optics (and diffraction/Huygens principle), so a beam will only reduce the loss by a constant factor, but the area of the beam still increases by n^2 as it propogates.
  • posix_me_less 5y ago
    No, EM radiation beam still obeys inverse square law.