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Change in velocity?

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    When drawing a vector diagram, I have been told to use the tip-to-tail rule

    However, as per this attachment, the change in velocity (which is a vector) does not seem to use this rule. indeed change in v (the horizontal line) has magnitude VB - Va.

    Why is this?
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    (Original post by ilovemath)
    When drawing a vector diagram, I have been told to use the tip-to-tail rule

    However, as per this attachment, the change in velocity (which is a vector) does not seem to use this rule. indeed change in v (the horizontal line) has magnitude VB - Va.

    Why is this?
    It is using the tip-tail rule, it's just you're adding the wrong way round.

    Tip to tail is for a+b=c with the tails of a and c starting at the origin, and the tip of a and the tail of b coinciding, and the tips of b and c coinciding.

    for change in velocity the equation is va+dv=vb and as you can see from your diagram the tip of va and tail of dv do coincide
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    (Original post by The Mr Z)
    It is using the tip-tail rule, it's just you're adding the wrong way round.

    Tip to tail is for a+b=c with the tails of a and c starting at the origin, and the tip of a and the tail of b coinciding, and the tips of b and c coinciding.

    for change in velocity the equation is va+dv=vb and as you can see from your diagram the tip of va and tail of dv do coincide
    oh I see

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