physics

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two objects are thrown from the top edge of a cliff with a speed of 10 m/s. one object is thrown straight down and the other straight up. if the first object hits the ground in 4.0 second, the second hits the ground in ________ seconds after the first object.

  • physics -

    Assume no air resistance.

    For the object thrown downwards,
    t=4 s
    vi=-10 (+ve upwards)
    g=-9.8 m/s²
    S=vi*t+(1/2)gt²
    =-10*4+(1/2)(-9.8)(4²)
    =-118.4 m

    For the object thrown downwards,
    t=unknown
    vi=+10 (+ve upwards)
    g=-9.8 m/s²
    S=vi*t+(1/2)gt²
    -118.4=+10*t+(1/2)(-9.8)(t²) ...(1)

    Solving the quadratic equation (1), we get
    t=-4 or t=296/49

    Can you take it from here?

  • physics -

    sfdxgvh,jkk

  • physics -

    12

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