Motion of an object dropped from a descending and ascending helicopter

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    Helicopter Motion
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The discussion focuses on the motion of a mailbag dropped from a descending helicopter. The initial speed of the mailbag after being released is calculated to be 32.25 m/s. Participants discuss the kinematic equations needed to determine the distance between the mailbag and the helicopter after 2.95 seconds and the speed of the mailbag if the helicopter were ascending. Clarifications are made regarding the helicopter's steady descent and its instantaneous stop after one second. Ultimately, the participant resolves their confusion and finds the correct answers for both scenarios.
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1.
a) A small mail bag is released from a helicopter that is descending steadily at 3.34 m/s. After 2.95 s, what is the speed of the mailbag? The acceleration of gravity is 9.8 m/s2 . Answer in units of m/s

b) After the mailbag is dropped, the helicopter continues descending for 1 s but then stops. How far is the mailbag below the helicopter at 2.95 s? Answer in units of m

c) What would be the speed of the mailbag if the helicopter had been rising steadily at u = 3.34 m/s ? (Take down as positive.) Answer in units of m/s


2. vf = vi + at


3. I've already gotten the answer to a) which is 32.25m/s, but I do not know how to do b) or c) from my answer to a).
 
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donking225 said:
I've already gotten the answer to a) which is 32.25m/s, but I do not know how to do b) or c) from my answer to a).

For b), you need a kinematic equation (valid for constant acceleration) that involves distance (usually denoted s). Do you have any such?

c) is exactly the same as a) but with a different vi.
 
haruspex said:
For b), you need a kinematic equation (valid for constant acceleration) that involves distance (usually denoted s). Do you have any such?

c) is exactly the same as a) but with a different vi.

would this equation be appropriate for b) s=vi*t+1/2*at2
 
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For c) would I use -3.34 as the vi?
 
Thanks for the help, I've got c) correct but am still confused about b).
 
Find s for both objects, what is the difference?

Note that the helicopter is not in free fall... Descending steadily...

I am assuming that the helicopter does not undergo a constant acceleration up during the 1s. The way it is written implies to me the helicopter stops instantaneously after 1s.
 
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pgardn said:
Find s for both objects, what is the difference?

Note that the helicopter is not in free fall... Descending steadily...

I am assuming that the helicopter does not undergo a constant acceleration up during the 1s. The way it is written implies to me the helicopter stops instantaneously after 1s.

Thanks, looks like I missed the obvious. I got the correct answer now.
 
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