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Suppose you stand in a basket and you try to pull the handles of the basket. Will you be able to lift the basket from ground?

Similarly, Baron Münchhausen allegedly pulled himself and the horse on which he was sitting out of a swamp by his own hair. Is this possible?

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closed as not a real question by akhmeteli, user10851, user1504, Waffle's Crazy Peanut, twistor59 Jun 22 '13 at 6:37

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Can you be a bit more precise on what confuses you here? "please think carefully" suggest that when you thought about it there was some contradiction. (Note that you can leave comments on your own question and answers to them, and edit your posts). It is also helpful to provide a less generic question title $\endgroup$ – Tobias Kienzler Jun 20 '13 at 13:23
  • $\begingroup$ @TobiasKienzler I edited it to remove that comment. I figured it was put at the end of the question by the professor, not the asker here. $\endgroup$ – Pricklebush Tickletush Jun 20 '13 at 13:36
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    $\begingroup$ I'd suggest actually performing this experiment if it is confusing. $\endgroup$ – Jerry Schirmer Jun 20 '13 at 14:00
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    $\begingroup$ @JerrySchirmer Good point, in contrast to the Münchhausen experiment this one is actually one where one can safely say "Kids, do try this one at home" $\endgroup$ – Tobias Kienzler Jun 20 '13 at 14:06
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    $\begingroup$ @SahilChadha If you are jumping then you are not technically standing inside of it $\endgroup$ – jeanqueq Jun 20 '13 at 16:01
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Yes, with a pulley:

enter image description here

(I'm aware this is cheating. This is my lawyerly interpretation of "pulling the handles of the basket.") It's instructive to consider why this works while pulling directly on the handles doesn't... or prove that this doesn't work :D

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    $\begingroup$ Very nice solution :-) $\endgroup$ – Tobias Kienzler Jun 20 '13 at 14:30
  • $\begingroup$ well this is cheating to do it like this you don't need a pulley. you can put a small child in basket and the child will will hold the basket with one hand and with the other hand his daddy can pull him and and basket up.basically you are using external forces. $\endgroup$ – Sahil Chadha Jun 20 '13 at 15:37
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    $\begingroup$ @SahilChadha Nope, you're just redirecting your own forces. If you do count constraining forces of course, then putting the basket in the floor was already cheating... $\endgroup$ – Tobias Kienzler Jun 21 '13 at 7:27
  • $\begingroup$ However, this doesn't explain why the intended idea -- pulling directly on the handles with your arms -- doesn't work. $\endgroup$ – The_Sympathizer Jan 24 '16 at 7:01
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This is a newton's third law problem, I'm having a hard time thinking of a way to explain this but because the forces of you pulling up will also be equal to the force of your feet pushing down the net force is equal to zero and there is no net external force, there will be no change in acceleration. I find it best to draw out free body diagrams for problems like this.

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    $\begingroup$ Welcome to physics.SE! And here's your first upvote :-) $\endgroup$ – Tobias Kienzler Jun 20 '13 at 13:34
  • $\begingroup$ well in this problem if you take yourself and the basket as a system then the only forces are gravity and normal reaction from ground. so maybe we can adjust the normal reaction so that the basket rises. $\endgroup$ – Sahil Chadha Jun 20 '13 at 15:33
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    $\begingroup$ @SahilChadha Again I would recommend drawing a free-body diagram. To beter understand this problem consider Newton's third law: When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction to that of the first body. Now let's look at the forces on the basket involved in understanding this problem. 1. Gravity (down) 2. Person's Weight(down) 3. Normal force(up) Now because there is no acceleration we know that the net force on the basket is equal to zero. Now lets begin pulling on the handles. $\endgroup$ – jeanqueq Jun 20 '13 at 15:48
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    $\begingroup$ What are the forces here? 1. Gravity(down) 2. Person's weight(down) 3. Normal force (up) Ok looks goodnow what else do we have. 4. Pulling up(up). **Now that we have applied a force on the basket, we know by Newton's third law there will be an equal opposite reaction. Where is that reaction? Down ** In fact it will be the exact magnitude of the force you have going upwards onto the basket going downwards. So we are left with the same situation as before: a net force of zero => acceleration of zero => no upwards motion. $\endgroup$ – jeanqueq Jun 20 '13 at 15:57
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    $\begingroup$ @SahilChadha Just get in the bloody basket and try it! :-P $\endgroup$ – Tobias Kienzler Jun 21 '13 at 7:34
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You pull the handles, the handles transmit that upwards-pointing force to the basket's bottom, which in turn transfers the force against your feet. On the other hand, your body provides the counter-force (actio=reactio) to that pulling, i.e. the stronger you pull the handles, the stronger your feet push down the bottom. The forces just cancel one another. This is by the way independent of the presence of gravity, where your body's gravitational force on the basket bottom is cancelled by the constraining force of the floor.

edit If you allow pulling so hard that the bottom tears apart, then you can of course lift the no longer intact basket from the ground. Or you could simply jump or step out of it...

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    $\begingroup$ In Greece we have a saying " the drowning man pulls himself by the hair" ( ο πνιγμένος απο τα μαλιά του πιάνεται) ; and in english there is the saying, again by a drowning analogy, or floundering in quicksand/bog: "pulling oneself up by the boot straps" ( which gave the name to a theoretical method of calculation :) ) $\endgroup$ – anna v Jun 20 '13 at 14:01
  • $\begingroup$ @annav Ah yes, good old Münchhausen :-) That's of course one origin of the term bootstrapping $\endgroup$ – Tobias Kienzler Jun 20 '13 at 14:08

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