What is magnitude?

  1. Actually i have just been to class 11th so i m not clear about magnitude so please help me in knowing magnitude and magnitude of displacement...
     
  2. jcsd
  3. CompuChip

    CompuChip 4,297
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    Basically, magnitude just means how big it is.
    If you have a vector (in, say, three dimensions) [tex]\vec x = (x_1, x_2, x_3)[/tex] then the magnitude of that vector is given by (Pythagoras): [tex]|\vec x| = \sqrt{x_1^2 + x_2^2 + x_3^2}[/tex].
     
  4. still not very clear how it is related to distance and displacement........then wt is magnitude of displacement.
     
  5. tiny-tim

    tiny-tim 26,043
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    Welcome to PF!

    Hi nehach ! Welcome to PF! :smile:

    "magnitude" is a long word which means something very simple.

    As CompuChip says, it just means how big something is.

    For example, if something is displaced along the x-axis by 3, then the magnitude of its displacement is also 3.

    But if something is displaced along the x-axis by -3, then the magnitude of its displacement is still 3. :smile:

    (magnitude is always positive, or zero.)
     
  6. Displacement is a vector quantity defined as the change in position - from an initial point i to a final point f. Its magnitude is the length of the straight line between i and f and its direction is from i to f. The actual path taken is irrelevant.
    Distance is a scaler quantity defined as the path length, i.e., it does depend on the actual path taken. Distance only equals the magnitude of the displacement for straight line paths.
    Hope this hepls :smile:
     
  7. if a person start from i and reach to f
    distance between i and f is 5 km

    i ----------5KM------------f

    now kindly tell me what is magnitude and what is displacement
    kindly tell me the formula how to calculate both of them

    because i am confisued in this
     
  8. tiny-tim

    tiny-tim 26,043
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    Hi nehach! :smile:

    Displacement: 5 km East.

    Magnitude: 5 km.
     
  9. thanks tiny-tim now its clear to me
     
  10. hey could u plz give me ur gmail id so that instead of wasting our time
    we can discuss any problem directly
    if u think ok
    kindly give me ur gmail id

    and kindly tell me the formula of calulating both displacement and magnitude
     
  11. Displacement is a vector quantity. It has direction and magnitude. The absolute quantity of vector is its magnitude.
    You can use the formula posted by CompuChip to calculate it
    Sorry if I said something wrong
     
  12. rcgldr

    rcgldr 7,539
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    Simpler still, magnitude is the size or length (always positive or zero) of a vector, independent of the vector direction. "Displacement" in Newtonian physics, is a vector, and has two elements, a signed length (positive, negative, or zero) and a direction.
     
  13. thanks jeff i got it
     
  14. symbolipoint

    symbolipoint 3,226
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