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    A particle is projected upwards at 12ms-1 from a point F. How long does it take to return to F
    The answer is 2.45 but how do I get that
    S=0 u=12 a=-9.8
    0= 12xt -1/2x9.8xt^2
    0=12t-4.9t^2
    I don't know where to go from there
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    We only have one variable left, being t. When we only have one variable left, we try to solve for t. Do you know how we can do this?
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    Use the equation v = u + at.
    12/9.81 = 1.223...
    Because it goes up and then comes back down you multiply by 2
    so 1.223... * 2 = 2.446.... or 2.45
 
 
 
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