Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Vectors, line contained within plane

  1. Oct 29, 2008 #1
    1. The problem statement, all variables and given/known data

    It seems to be obvious. But would like to check that for a line to be contained in a plane it needs to be parallel. Correct?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 29, 2008 #2


    User Avatar
    Science Advisor

    parallel to what?

    Parallel to the plane? No, a line that is contained in the plane is not, by definition, "parallel" to that plane. In order to be parallel, the line must have no points in common with the plane which is clearly not true if it is contained in the plane.

    It is true that if a line is contained in a plane then its direction vector is perpendicular to the normal vector of the plane.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook