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    Could someone help me with part c of this question I don’t even know where to start
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    (Original post by Mf1999)
    Could someone help me with part c of this question I don’t even know where to start
    First of all.. how did you manage to capture such a blurry image in 2018?
    Not sure if u have learned about the dot product of vectors, but that is one way to find the velocity perpendicular to the initial velocity. Here are the steps:
    1. Split the initial velocity into horizontal and vertical components. (Let's call them Ux & Uy)
    2. The velocity at Q will be Vx & Vy, after using dot product on the 2 vectors, for both of them to be perpendicular, Ux * Vx + Uy * Vy =0
    3. Solve the equation in 2. and get the displacement from the velocity (Vy & Vx).

    original velocity = ai + bj

    perpendicular velocity = bi - aj

    acceleration = 0i - 9.8j

    bi - aj = ai + bj + (0i - 9.8j)t

    ====> b - a = 0

    a = 7
    b = 7c


    i am actually getting a value for c

    c = 1
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