1d Kinematics formula question

AI Thread Summary
To solve the problem of a package dropped from a helicopter ascending at 2.50 m/s from a height of 120 m, the correct kinematic equation to use is 0 = 120 + 2.50T - 0.5(9.8)T^2. This equation accounts for the initial upward velocity of the package and the downward acceleration due to gravity. The resulting quadratic equation can be solved for time, yielding a realistic answer of approximately 5.0 seconds, not 50 seconds. The calculation of 0.26 seconds using 2.50/-9.8 is incorrect as it does not consider the initial height or the upward velocity. Thus, the time for the package to reach the ground is around 5 seconds.
RedBurns
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Could someone please help me in determine the correct formula(s) to answer this problem?

A helicopter is ascending vertically with a speed of 2.50 m/s. At a height of 120 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground?

I know:
Acceleration -9.8 m/s/s
Initial position 120m
Final postion 0m
velocity 2.50m/s

I need to determine time.

------------------------------------------
Would 2.50/-9.8 give me the correct time of .26 seconds or have I missed something here?

or would I use 0=120 + 2.50T + .5(-9.8)T^2 giving the time of 50 seconds?
 
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Does 50 seconds seem reasonable?
 
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