Which statement is true about unit vectors i, j, and k?

Which statement is true about unit vectors i, j, and k?





a) Their directions are defined by a left-handed coordinate system.





b) The angle between any two is 90 degrees.





c) Each has a length of 1m.





d) If i is directed east and j is directed south, k points up out of the surface.





e) All of the above.

Which statement is true about unit vectors i, j, and k?
(b) is true. (c) is not true and therefore (e) is not true.
Reply:a) FALSE - it's defined by a right-handed coordinate system





b) TRUE





c) FALSE - each has a unit length of 1, not necessarily 1 m





d) FASLSE - if i is east, and j is south, k should point down





e) obviously FALSE
Reply:All of the above.


:)