1d Kinematics formula question

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SUMMARY

The discussion focuses on solving a 1D kinematics problem involving a helicopter ascending at 2.50 m/s and a package dropped from a height of 120 m. The correct approach to determine the time it takes for the package to reach the ground involves using the kinematic equation: 0 = 120 + 2.50T - 0.5(9.8)T². Solving this quadratic equation yields a time of approximately 5.06 seconds, not 0.26 seconds or 50 seconds, which are incorrect calculations based on misapplication of the kinematic formulas.

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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?
 
Last edited:
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Does 50 seconds seem reasonable?
 

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