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Ball thrown off a building time question Watch

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    Been given this question, and I'm sure it's to be solved with a quadratic equation but it's not really working out for me so far.

    A ball's been thrown off a building and it's going at 60 km per hour, the building is 100 meters tall and the distance before it reaches the ground is;

    d = ½gt^2 + vt

    g = gravity and it's 10 ms^-2
    t = time in seconds
    v = initial velocity

    I've to find the time for the ball when it's dropped ¼ the height of the building.

    so I got;

    5t^2 + 60t - 25 = 0

    Am I on the right track?
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    (Original post by Brainfrozen)
    Been given this question, and I'm sure it's to be solved with a quadratic equation but it's not really working out for me so far.

    A ball's been thrown off a building and it's going at 60 km per hour, the building is 100 meters tall and the distance before it reaches the ground is;

    d = ½gt^2 + vt

    g = gravity and it's 10 ms^-2
    t = time in seconds
    v = initial velocity

    I've to find the time for the ball when it's dropped ¼ the height of the building.

    so I got;

    5t^2 + 60t - 25 = 0

    Am I on the right track?
    You should probably covert from km/h to m/s before plugging that speed in since right now the equation doesn't make sense, otherwise you're on the right track.
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    (Original post by RDKGames)
    You should probably covert from km/h to m/s before plugging that speed in since right now the equation doesn't make sense, otherwise you're on the right track.
    It's sorted, thanks for your help!
 
 
 
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