1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Vector - points in same direction

  1. Oct 23, 2008 #1
    I don't know how to make the vector arrow on top of the letter so I just underlined the vectors. Also I don't know how to make the square root symbol so I just type sqrt for it.

    1. The problem statement, all variables and given/known data
    Which points in the same direction as V = (-sqrt2, sqrt3, sqrt5)
    a) 1/10 V
    b) sqrt10/10 V
    c) sqrt10 V
    d) sqrt 10 V

    2. Relevant equations

    3. The attempt at a solution
    I am not sure where to start other than calulating the sqrt of 2,3, and 5. My best guess would be c but I need to know why if that is correct or some help figuring it out.
    Please help,
  2. jcsd
  3. Oct 23, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi Marion! Welcome to PF! :smile:

    (have a square-root: √ :smile:)

    On this forum, type vectors in bold. :wink:
    (c and d look the same :confused:)

    As you probably know, on this forum we don't tell you the answer, we just try to nudge you in the right direction. :wink:

    What tests do you know for two vectors to be pointing in the same direction? :smile:
  4. Nov 3, 2008 #3
    It is a good idea to make carefull use of parentheses so that there is no
    ambiguity as to the meaning of an expression.

    Consider that for positive constants k, and vectors v, k v is in the same direction of v.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook