Unsolvable Puzzle: Can a Puck Stop in 0.42s?

  • Thread starter Thread starter chengbin
  • Start date Start date
  • Tags Tags
    Puzzle
Click For Summary
SUMMARY

The discussion revolves around a physics problem involving a puck of mass 30g sliding across rough ice with a frictional force of 0.2N. The puck, initially moving at 10km/h, takes 0.42 seconds to stop after reaching the ice patch. The confusion stemmed from the interpretation of the term "hit," which was clarified to mean "reach" rather than an instantaneous stop. This understanding resolved the initial doubts about the solvability of the problem.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Basic knowledge of frictional forces
  • Familiarity with kinematic equations
  • Concept of colloquial language in physics contexts
NEXT STEPS
  • Study Newton's second law of motion and its applications
  • Learn about calculating frictional forces in different materials
  • Explore kinematic equations for motion with constant acceleration
  • Research the impact of colloquial language on scientific communication
USEFUL FOR

Students studying physics, educators teaching motion concepts, and anyone interested in the application of kinematics in real-world scenarios.

chengbin
Messages
26
Reaction score
0

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?

Homework Equations


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.
 
Physics news on Phys.org
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" )
 
Last edited by a moderator:
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.
 
Last edited by a moderator:

Similar threads

  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
Replies
3
Views
7K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K
Replies
4
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K