Proof that a projectile comes to rest in a finite distance

AI Thread Summary
The discussion centers on proving that a projectile in two-dimensional motion comes to rest in a finite distance when its velocity is greater than zero. Participants highlight the importance of understanding the equations of motion, particularly in the context of linear drag forces. There is confusion regarding the applicability of the equations presented, as they suggest that the projectile will not come to rest in the vertical direction. The need for a complete and accurate statement of the original question is emphasized to facilitate better assistance. The conversation underscores the necessity of demonstrating an understanding of the problem before seeking help.
dk123
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Homework Statement
How do I prove that a projectile in a two-dimensional trajectory motion comes to rest in a finite distance when v>0
Relevant Equations
Projectile Motion Equation
equation of motion :
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while
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dk123 said:
Homework Statement:: How do I prove that a projectile in a one-dimensional trajectory motion comes to rest in a finite distance when v>0
Relevant Equations:: F_net = mg-bv

equation of motion dervinghttps://www.physicsforums.com/attachments/262298

https://www.physicsforums.com/attachments/262295 and https://www.physicsforums.com/attachments/262296 => https://www.physicsforums.com/attachments/262297
The equations you posted look like falling through a medium with linear drag. That is clearly not going to come to rest in consequence of those equations. It will come to rest, one presumes, when it lands.
Please post the exact question as given to you.
 
haruspex said:
The equations you posted look like falling through a medium with linear drag. That is clearly not going to come to rest in consequence of those equations. It will come to rest, one presumes, when it lands.
Please post the exact question as given to you.
I fixed the question!
 
dk123 said:
Homework Statement:: How do I prove that a projectile in a two-dimensional trajectory motion comes to rest in a finite distance when v>0
Relevant Equations:: Projectile Motion Equation

equation of motion :
View attachment 262306
while
View attachment 262305
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View attachment 262309
:welcome:
What have you tried?
Where are you stuck?

According of rules of this forum, you must show an attempt at solving/understanding the problem before we can give any help.
 
dk123 said:
I fixed the question!
Only partly. You have posted some equations and your own paraphrase of the question. This still does not make sense since it is obvious from those equations that it will not come to rest in the y direction.
Please post the complete statement of the question as provided to you.
 
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