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Will the time of landing be the same if ...

  1. Sep 20, 2015 #1
    if we throw a cannon ball from a height in projectile motion and an egg from the same height in projectile motion will it land at the same time?
     
    Last edited by a moderator: Sep 20, 2015
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  3. Sep 20, 2015 #2

    Suraj M

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    yes it would, ignoring friction of course and if they follow the same path or if both were launched with the same vertical component of the imparted initial velocity.
     
  4. Sep 20, 2015 #3

    phinds

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    "Throw" is a very vague way to state the problem. If you throw an egg with as much force as you can muster and similarly throw a cannon ball with as much force as you can muster, and you throw them both in a downwards direction, then no they will not land at the same time because you will have imparted a greater speed to the egg. If you throw them horizontally, then they will land at the same time but with the egg farther away from you. Both these statements assume you can throw them both at the same time, presumably one with the left hand and one with the right, since you have not said that you throw them at the same time, and if not, then they will land at times that depend on the time you throw them.

    My point here is that it is very important to be precise in stating problems if you want a well determined answer. A better way to state this problem is "release simultaneously". This takes care of both the initial timing problem, which you did not well define, and the initial velocity problem, which you also did not well define.
     
  5. Sep 20, 2015 #4

    They would be released simultaneously , from same height , thus having same initial velocity and with equal force
     

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  6. Sep 20, 2015 #5

    phinds

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    And my point was that you didn't say that in the original question. Under those conditions then they would land at the same time.
     
  7. Sep 20, 2015 #6
  8. Sep 20, 2015 #7
    But they would not be subject to the same force. The cannon ball is presumably much heavier, so it would experience a proportionally greater gravitational force. Since the gravitational forces on each object would proportional to each objects mass, the acceleration due to gravity would be the same. The forces, however, are not the same.
     
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