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Acceleration Time graph of a parachutist who pulls his chute after jumping Watch

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    The image inserted is basically the question. Im thinking its C due to the motion i picture in my head (as seen in movies when a guy pulls a chute etc) However, im not 100% sure. Can someone confirm/ or let me know if im wrong. Thanks
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    It's wrong. C shows that there is constant acceleration then when the chute is pulled there is a large drop in acceleration but then rapidly rises.
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    (Original post by Vikingninja)
    It's wrong. C shows that there is constant acceleration then when the chute is pulled there is a large drop in acceleration but then rapidly rises.
    So the answer should be D, since the acceleration increases then becomes constant ?
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    (Original post by ksrw395)
    So the answer should be D, since the acceleration increases then becomes constant ?
    Actually no sorry I'm an idiot it is C sorry. Thought that on C it went back up to its original but looked second time and it rose up and stopped at 0. Others are incorrect since they show an increase in acceleration when its in the positive.
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    (Original post by Vikingninja)
    Actually no sorry I'm an idiot it is C sorry. Thought that on C it went back up to its original but looked second time and it rose up and stopped at 0. Others are incorrect since they show an increase in acceleration when its in the positive.
    Haha no problem
    Thanks!
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    C is correct.

    The jumper accelerates under constant gravitational acceleration (velocity increases) until his chute opens.

    As the chute opens, he decelerates (curve goes negative) rapidly and attains a constant velocity at which time the acceleration is zero.
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    (Original post by uberteknik)
    C is correct.

    The jumper accelerates under constant gravitational acceleration (velocity increases) until his chute opens.

    As the chute opens, he decelerates (curve goes negative) rapidly and attains a constant velocity at which time the acceleration is zero.

    Sorry this is an old post, but what about if air resistance is taken into account?
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    (Original post by marinacalder)
    Sorry this is an old post, but what about if air resistance is taken into account?
    That of the parachute is
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    (Original post by marinacalder)
    Sorry this is an old post, but what about if air resistance is taken into account?
    The deceleration/negative acceleration is caused by increased air resistance.
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    (Original post by marinacalder)
    Sorry this is an old post, but what about if air resistance is taken into account?
    air resistance before the diver opened his chute would round off the start of the 'knee' a bit - terminal velocity of a skydiver is ~50 m/s so after 2.5 seconds the diver would be going maybe half that, so getting about 1/4 of the resistance at terminal velocity... air resistance would be starting to be get quite significant.
 
 
 
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