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: The angle between P and Q?

  1. Jul 13, 2018 at 6:45 AM #1
    • Member has been warned for showing no own effort.
    1. The problem statement, all variables and given/known data
    The resultant R of vectors P and Q is perpendicular to P and R=P both, then the angle between P and Q is what?
    Now, what is the concept behind it? Could you provide me with an image of the resultant perpendicular to two vectors so that I can understand the concept and start solving the problem?

    2. Relevant equations


    3. The attempt at a solution
     
  2. jcsd
  3. Jul 13, 2018 at 6:48 AM #2

    stevendaryl

    User Avatar
    Staff Emeritus
    Science Advisor

    What do you mean by "is perpendicular to P and R=P both"? I don't know how to parse that.
     
  4. Jul 13, 2018 at 7:01 AM #3
    nither I understand what it means. The question says like this.
     
  5. Jul 13, 2018 at 7:16 AM #4

    mjc123

    User Avatar
    Science Advisor

    Perhaps it means "R is perpendicular to P and |R| = |P|". Or perhaps "R is perpendicular to P and R = P". Or whatever notation. That is, the vector R is at right angles to the vector P, and the length of R equals the length of P.
     
  6. Jul 13, 2018 at 7:19 AM #5

    stockzahn

    User Avatar
    Gold Member

    I agree with stevendaryl, the question is not easy to understand formulated like this, but here is my guess:

    The resultant vector ##\vec{R}## is the sum of the two vectors ##\vec P ## and ##\vec Q ##. You know the direction and the length of ##\vec P ##, where the latter is identical with the length of ##\vec R ##. Therefore you know the lengths of two vectors and their angle with respect to each other. By drawing this constellation, there is only one possibility for ##\vec Q ## to fit between them. Try to draw it, show your attempt and it's easier to help you.
     
  7. Jul 13, 2018 at 8:27 AM #6

    fresh_42

    User Avatar
    2017 Award

    Staff: Mentor

    Please report to the mentors those cases, in which the OP doesn't show any effort to tackle his problem, instead of answering it. If you think it is a general problem of understanding rather than a homework problem, then please also report it, such that we can move it to a technical forum.

    @Indranil : If you're in doubt what to do, you can always ask in advance for guidance by a mentor, or report your own post to be evaluated.

    Thanks for your understanding.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook