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Physics again watch

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    Calculate the potential in the earths gravitational field a the position of:
    a) a geosyncrhonous orbit

    help:|
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    use GMm/r² = mv²/r, and v = 2pi r/T, where T is 24 hours (in seconds), to work out the radius of a geosynchronous orbit, then use Vg = -GM/r
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    Thank you!
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    A 320kg satllite is lifted from an orbity 1.2x10^6 above the surface of the earth to one which is 3.6x10^7 above the earths surface.

    Calculate:
    a) the initial speed of the satellite

    Isnt this just v^2 = Gmearth/r ???Im not getting the right answer
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    Got it now, I forgot to add the radius of the earth
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    *screams*

    Using the info given above: calculate the change in PE when the satellites orbit is changed.

    Ep = Gm1m2(1/r1-1/r2)

    Why am I getting the wrong answerrrrrrrrrrr???
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    (Original post by imasillynarb)
    *screams*

    Using the info given above: calculate the change in PE when the satellites orbit is changed.

    Ep = Gm1m2(1/r1-1/r2)

    Why am I getting the wrong answerrrrrrrrrrr???
    Won't the change in PE be the same as the change in KE....using mv^2/r=Gm/r^2..........should give you the velocity and then u can find out the KE hence the PE............I think .....
 
 
 
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