I know that the reason I couldn't lift myself up(without the help of any items or a pulley system)was due to that my force was internal and there is a reaction force. However, assuming that somebody attempts to lift me up, wouldn't there also be a reaction force that prevents him from doing so?
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3Can you climb up a rope? – Cosmas Zachos May 19 '21 at 17:46
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Possible duplicates: https://physics.stackexchange.com/q/216094/2451 , https://physics.stackexchange.com/q/68629/2451 , https://physics.stackexchange.com/q/78470/2451 and links therein. – Qmechanic May 19 '21 at 17:52
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2I lift myself up every morning when I get up out of bed. – my2cts May 19 '21 at 17:53
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My bad, should've expressed it a bit better. The 'lift' i'm referring to is that assuming I am standing still on the ground and I try to lift myself (like pulling my hair or put my hands around my waist in an attempt to 'lift' myself off the ground), without the help of other items – Newton Hofsteider May 19 '21 at 17:59
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Does this answer your question? Given Newton's third law, why are things capable of moving? – BioPhysicist May 19 '21 at 18:40
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You have already given the answer, it's Newtons third law actio = reactio. If you apply a force to yourself to lift you up, there is an equal force pressing you down. If another person lifts you up, then he is pressed down to the ground.
Actually you can kind of "lift up" yourself in the meaning of pressing up yourself, but only if a part of you (e.g legs or arms) is touching the ground. You are doing that all the time when walking.
Charles Tucker 3
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Of course you can lift yourself up. Have a look at this video where a mom is using the tree house pulley chair to lift herself to the tree house.Force is a vector, it is all a matter of the direction of the force applied, not just its magnitude.
anna v
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Sorry, I should have expressed it with more detail. For this question, I'm talking about lifting myself without the help of anything, like pulling my hair in an attempt to lift myself. – Newton Hofsteider May 19 '21 at 18:08
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But if you think a bit about it you could use the pulley to pull yourself by the hair. – anna v May 19 '21 at 18:34