A spacecraft descends vertically near the surface of Planet X. An upward thrust of 25.0 kn from its engines slows it down at a rate of 1.20 m/S2, but it speeds up at a rate of 0.80 m}S2 with an upward thrust of 10.0 kn. (a) In each case, what is the direction of the acceleration of the spacecraft? (b) Draw a free-body diagram for the spacecraft. In each case, speeding up or slowing down, what is the direction of the net force on the spacecraft? (c) Apply Newton s second law to each case, slowing down or speeding up, and use this to find the spacecraft s weight near the surface of Planet X. |

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