physics

A stone is dropped from a 100m bridge. How long does it take the rock to reach the ground?

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  1. Vertical Going down postive
    d=100m
    a=+9.8m/s2
    V1=0

    Use the formula
    d=v1t=1/2 a t*2
    100= 1/2 (9,8) t*2
    100=4.9t*2
    Divide 4.9 from both sides
    20.4=t*2
    square root 20.4
    t=4.51s

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