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Homework Help: Centripetal acceleration of the stone

  1. Oct 4, 2004 #1
    Would someone plz show me how to do these problems below. Thanks.
    1) An Earth satellite moves in a circular orbit 640km above Earth's surface w/ a period of 98.0min. What are (a) the speed and (b) the magnitude of the centripetal acceleration of the satellite?

    2) a boy whirls a stone in a horizontal circle of radius 1.5m and at height 2.0 above level ground. the string breaks, and the stone flies off horizontally and strikes the ground after traveling a horizontal distance of 10m. What is the magnitude of the centripetal acceleration of the stone while in circular motion?
     
  2. jcsd
  3. Oct 5, 2004 #2
    #1
    Use [tex]v=\frac{2\pi r}{T}[/tex] with
    v= the speed of the satellite
    r= the radius of the circular orbit of the satellite
    T= the period taken by the satellite to make one revolution

    Use [tex]a=\frac{v^2}{r}[/tex] with
    a= the magnitude of the centripedal acceleration of the satellite
    v= the speed of the satellite
    r= the radius of the circular orbit of the satellite

    #2
    Use [tex]a=\frac{v^2}{r}[/tex] with
    a= the magnitude of the centripedal acceleration of the stone
    v= the speed of the stone when the string breaks
    r= the radius of circular path of the stone
    Manipulate the formula to obtain v which is the horizontal initial velocity of the stone when the string breaks. The rest is about 2D projectile motion.
     
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