What are the two forces that act on the orbit of a planet? A) Velocity of planet and gravity between sun and planet.
B) Gravity between the aphelion and perihelion.
C) Gravity between planet and sun and the velocity of the sun.
D) Orbits of other planets and gravity between sun and planet.
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Wo small variable-thrust jets are actuated to keep the spacecraft angular velocity about the z-axis constant at ? 0 = 1.16 rad/s as the two telescoping booms are extended from r1 = 1.18 m to r2 = 4.69 m at a constant rate over a period of 124 seconds. the small 19-kg experiment modules at the ends of the booms may be treated as particles, and the mass of the rigid booms is negligible. determine the necessary thrust t for each jet as a function of time where t = 0 is the time when the telescoping action is begun. after you have the general expression for t, answer the questions. show work.