Another question,(hope it isnt boring)

  • Context: High School 
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Discussion Overview

The discussion revolves around a hypothetical scenario involving a canoeist who loses a hat in a river while rowing upstream against a current. Participants explore the implications of the scenario, focusing on the time it would take to retrieve the hat, the nature of motion in an inertial frame, and the assumptions made about the situation.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that the hat's loss and retrieval is a viewpoint question, referencing a book related to mathematical reasoning.
  • Another participant argues that no one would wear a valuable hat while canoeing, implying that retrieving it is irrelevant.
  • A different viewpoint claims that if the turnabout is instantaneous and acceleration-free, the river's current and gravity become irrelevant, focusing instead on the hat's position.
  • Some participants discuss the hat's position relative to the river flow, suggesting that it remains at rest in an inertial frame, thus simplifying the problem to a matter of time.
  • One participant asserts that if the canoeist does not paddle after the hat, they will not move relative to the hat's frame, while another calculates that rowing at a specific speed would allow retrieval in a certain time frame.
  • There is a contention regarding the relevance of gravity and current in an acceleration-free scenario, with some arguing that these factors do not affect the outcome.
  • A humorous suggestion is made about simply picking up the hat from the boat or waiting for it to float back, questioning the assumptions about the current's direction.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the scenario, with no consensus on the time it would take to retrieve the hat or the assumptions about the conditions of the problem.

Contextual Notes

Participants highlight various assumptions, such as the nature of the turnabout, the relevance of gravity and current, and the initial conditions of the scenario, which remain unresolved.

idontthinkright
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You are canoeing upstream of a river,the current against you is 3 mph.You are rowing at 4 and 1/4.Your hat falls onto the water and only after 45 minutes,you then realize that it is gone.in a split second you make an instantaneous,acceleration-free turnabout to get your hat.

How long will it take for you to get it back?

(this looks like a math question,but trust me it isnt.)
 
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It's a viewpoint question. Did you read the fine book Count Down (about the Math Counts program)?
 
i haven't read any,but i have read richard feynmans "genius" book,an autobiography of his life.

By the way,have you found the answer?:smile:
 
No one would wear a valuable hat whilst canoeing, so it wouldn't matter if you didn't get the hat back. Therefore, no time, because I wouldn't get the hat. The. End.
 
you'd never get your hat because you'd always be traveling at the same speed after it with the current and be 45 mins behind, as no mention of any paddling was made in an attempt to retrieve the hat. Best guess anyway. that or an instantaneous acceleration free turnabout is impossible.
 
Kurdt you almost got it correct(darn).when instantaneous free-acceleration turnabout is possible,the river and gravity becomes irrevelent.Focusing your point of view onto the hat..and you will see it keeping still.Realising it is missing,it will take you 45 mins to row back to where you lost it About the paddling thing,if it is acceleration-free,your own inertia will need no paddling,thats the part you sort of got correct. :smile:
 
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The hat is at rest wrt the river flow (inertial frame!). So wrt the hat all the speeds go away and it's just a time problem.
 
Etak said:
No one would wear a valuable hat whilst canoeing, so it wouldn't matter if you didn't get the hat back. Therefore, no time, because I wouldn't get the hat. The. End.

I agree.Just buy another hat. :-p
 
How much is that ?Is that cheap ?
If that is, I suggest you buy 1000 hats and use one by one till the day you go to he||.
 
  • #10
i don't know about you guys, but I am going to post a few more questions.By the way to find the answer you NEED the hat for the question.It don't matter whether its logical,or not.It is focused rather on inertial frame and point reference.
 
  • #11
The hat will be 4950 ft from you when you make the turnabout. How long it takes you to get to it depends on the speed you move wrt to the hat's inertial frame. If you simply turn around but don't paddle after it, you will not move at all wrt that frame. If you continue rowing at 4 1/4, you'll get there in 13.2 minutes (to three significant figures).
 
  • #12
lol loseyourname, once you start calculating,you're already WRONG. the speeds, current,gravity are all irrelevant when it is acceleration-free.Without gravity, the hat will be in mid-air and stuck there,and gravity doesn't affect your current rowing and you continue rowing with no resistance whatsoever.The final answer will still be 45 mins.4950ft may be part of the process but in acceleration-free environment,(like self-adjoint said)it becomes only a time problem.By the way,the question itself in actual testing is given only 45 seconds to answer.
 
  • #13
The hat fell into the boat which had water in it. Pick it up and place it on you head.

or

Turn the boat around drop anchor and wait until the hat comes to you, who said you were going against the current? The current against you is 3mph either way.

The third is the normal obvious assumption.

Books are what you need while you don't open the one you are born with. Real wisdom, mine, it comes from the water.
 

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