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Free fall motion from airplane

  • Thread starter bdh2991
  • Start date
  • #1
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Homework Statement



A package is dropped at time t = 0 from a helicopter that is ascending steadily at a speed vi.
What is the speed of the package in terms of V[itex]_{i}[/itex], g, and t?

Homework Equations



V (t) = V[itex]_{o}[/itex] + -9.8 t


The Attempt at a Solution



I thought it was the same as the normal equation for velocity such as stated above but with the different variables substituted for example:

|V| = V[itex]_{i}[/itex] + gt

except i got the answer wrong, then i tried putting a negative sign on the v[itex]_{i}[/itex] part but still got it wrong...help would be greatly appreciated.
 

Answers and Replies

  • #2
lewando
Homework Helper
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You are close. Speed is |v(t)|. Try putting the magnitude bars around your expression for v(t).
 
  • #3
103
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the magnitude bars are already there on the online hw, only the stuff to the right of the "=" sign is what i'm able to input....


nvm i see what your saying....but there was another part of the question in which the plane was descending and asked the same question and i got it right without putting the '|' around v(t)
 
Last edited:
  • #4
CWatters
Science Advisor
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Try

|V| = |Vi - gt|

or

|V| = |gt - Vi|
 
  • #5
103
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Try

|V| = |Vi - gt|

or

|V| = |gt - Vi|
tried both but neither worked...i really think it is just the stupid website that i have to do the hw on but i'm all out of chances so doesn't matter now lol thanks for the suggestions though
 

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