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Homework Help: Just a LIL Physics Help

  1. Mar 22, 2005 #1
    Just a LIL Physics Help :)

    Some odds of my homework I couldn't figure out,,, any help would be appreciated and REPPED

    1.
    Find the centripetal accelerations of a point on the Equator, due to the rotation of Earth about its axis.
    m/s2

    2.
    Two objects attract each other with a gravitational force of magnitude 0.99 10-8 N when separated by 19.6 cm. If the total mass of the two objects is 5.08 kg, what is the mass of each?
    kg (heavier mass)
    kg (lighter mass)

    3.
    A satellite moves in a circular orbit around the Earth at a speed of 5458 m/s.
    (a) Determine the satellite's altitude above the surface of the Earth.
    m
    (b) Determine the period of the satellite's orbit.
    h

    if needed
    mass of earth = 5.98 E 24
    Radius of earth = 6.38 E 6
    G = 6.67 E -11
     
  2. jcsd
  3. Mar 22, 2005 #2
    for 1. use the equation [tex] a_c = \frac{v^2}{r} [/tex] to find a, you need to find out at what speed you are rotating at. Thisnk about it, you know how long a day is, you know the earths radius. Solve the problem.

    for 2. use Newtons law of gravitational attraction: [tex] F_g = \frac{Gm_{1} m_{2}}{d^s} [/tex] you know the distance between the two, you know the G constant, you have the force. To solve for the mass inequality, just set up an equation for mass using 5.08-x and x as your two masses. Now solve for x.

    3. Ill let you ponder on that one by yourself. I alwready solved the first two for you, which I shouldnt have.

    Regards,

    Nenad
     
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