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Free-Falling Bodies. Objects Falling Straight Down. Points to consider: As the object falls, it has a constant acceleration due to gravity of 9.80 m/s 2 . If object is dropped, initial velocity = 0. If object is thrown down, then initial velocity is ……..
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Objects Falling Straight Down • Points to consider: • As the object falls, it has a constant acceleration due to gravity of 9.80 m/s2. • If object is dropped, initial velocity = 0. • If object is thrown down, then initial velocity is …….. • Final Velocity is velocity just as it hits the ground, not the velocity after it has come to a stop! • All 3 acceleration equations can be used, simply substitute the acceleration due to gravity(g) for a in the equations!!!
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Objects going up and back down!! • Points to consider: • 1st—Treat tossed object as two separate paths, one up and one down. • Object will have an initial velocity upward! • Final velocity on the upward path will be 0. • Initial velocity on the downward path will be 0. • Final object on the downward path will be = to the initial velocity on the upward path. • Time up = Time down • Distance up = Distance down
vf = # = vi = # • Notice anything about the velocities? • Directions are opposite!! • Therefore, we must make one of the two directions (-). • Because on our EOC, g = +9.80 m/s2, we will consider down the + direction and up and the (-) direction. dup = ddown tup = tdown vi = # = vf = #
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