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    I just can't seem to draw resultant velocity triangles correctly.
    I have just done a question from January 2006 and the mark scheme uses the diagramName:  Capture.PNG
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    (The question asks to find V).
    I however drew it differently so I still had an included angle but on my diagram that angle was 45.
    I just don't seem to be able to understand how you know where to draw the different velocities.
    Any advice
    Many thanks
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    (Original post by orange8120)
    I just can't seem to draw resultant velocity triangles correctly.
    Could you provide the question?
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    (Original post by Zacken)
    Could you provide the question?
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    (Original post by orange8120)
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    For 1 (a) (i), try to use trigonometry for right angled triangles. For part 1 (a) (ii), try now to use the fact that this a right angled triangle to work out v.

    For (b), a force diagram is certainly useful. You say in the OP you struggle with this. The way I would approach this would be to literally squash the forces together.

    So place the line for the velocity of the water going into the line representing the velocity of the boat. Then my resultant will be the line connecting these two vectors, so to make a resultant force triangle (see my diagram).

    This triangle is not right angled and so you need to consider how you work out the lengths of the sides of a right angled triangle. The angle between the two sides can be worked out using basic geometry.

    Let me know if you need any further help!
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