Unsolvable Puzzle: Can a Puck Stop in 0.42s?

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The discussion revolves around a physics problem involving a puck sliding across rough ice and the time it takes to stop due to friction. Initially, there is confusion about the term "hit," which some interpret as an instant stop, while others clarify it means the puck reaches the ice patch and decelerates. The frictional force acting on the puck is 0.2N, and it was initially moving at 10km/h. After clarification, participants agree that the problem is solvable, leading to a stopping time of 0.42 seconds. The conversation highlights the importance of understanding terminology in physics problems.
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Homework Statement



A puck of mass 30g slides across rough ice, experiencing a frictional force of 0.2N. If it was moving at 10km/h when it hit the ice patch, how long did it take to stop? How long was the ice patch?

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The Attempt at a Solution



I don't think this question is solvable or make any sense. If it hits something, it stops instantly, but the answers say 0.42 seconds.
 
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Hi chengbin! :smile:

This is colloquial English …

"hit" (here) means "reach" … it reaches the ice patch, and is slowed down while crossing it. :wink:

(see http://en.wikipedia.org/wiki/Colloquialism" )
 
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tiny-tim said:
Hi chengbin! :smile:

This is colloquial English …

"hit" (here) means "reach" … it reaches the ice patch, and is slowed down while crossing it. :wink:

(see http://en.wikipedia.org/wiki/Colloquialism" )


Thank you!

That solved the problem.
 
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