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Homework Help: Questions about Vectors.

  1. Sep 19, 2011 #1
    hi everyone, i was doing my physics homework and i had problems in these 2 MC quesitons.

    #1 A vector originally at a direction of 30°, when measured counter-clockwise with respect to the +x axis, is rotated a further 30° counter-clockwise.
    The magnitude of the vector will ...

    a.Increase by a factor of four
    b.Increase by a factor of two
    c.Remain the same
    d.Decrease by a factor of two
    e.Decrease by a factor of four

    #2 The components of vector are Ex = +150 N/C and Ey = -100 N/C.
    If we measure all angles with respect to the +x axis and counter-clockwise as the positive direction, the direction of is closest to:


    a. -326°
    b. -56°
    c. -34°
    d. +34°
    e. +304°
     
  2. jcsd
  3. Sep 19, 2011 #2
    1) What do you think?

    2) Draw the components.
     
  4. Sep 19, 2011 #3
    1) draw a 30 degree, and 60 degree angle. but think about this: does your magnitude have anything to do with the changing of angles?
     
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