Simple forces question

  • Thread starter dnt
  • Start date
  • #1
dnt
238
0
forgot some details to the question but thats ok because i have a general one: a puck is hit with an initial velocity of 5 m/s and comes to a stop some time later. the question is find the friction coefficient of the ice and puck.

anyways, when making a forces diagram, i know the friction points back but does anything point forward? is there a force pushing it (after its been hit) and if so, how do you find it?

what i did to solve it was say the net force equals Fpuck - Ffriction = ma

they gave the mass and i solved for acceleration using regular kinematics but i had to assume Fpuck was 0. is that true? the answer came out correct but i dont know why the Fpuck=0.
 

Answers and Replies

  • #2
dnt
238
0
and boy am i glad i didnt forget the p...
 
  • #3
Tom Mattson
Staff Emeritus
Science Advisor
Gold Member
5,549
8
dnt said:
forgot some details to the question but thats ok because i have a general one: a puck is hit with an initial velocity of 5 m/s and comes to a stop some time later. the question is find the friction coefficient of the ice and puck.

So far so good.

anyways, when making a forces diagram, i know the friction points back but does anything point forward? is there a force pushing it (after its been hit) and if so, how do you find it?

If it isn't being pulled, pushed, attracted by a magnet, etc then there is no force other than friction acting in the direction of motion.

they gave the mass and i solved for acceleration using regular kinematics but i had to assume Fpuck was 0. is that true? the answer came out correct but i dont know why the Fpuck=0.

It is correct, for the reason given above.
 
  • #4
dnt
238
0
excellent. thanks.
 

Related Threads on Simple forces question

  • Last Post
Replies
17
Views
2K
  • Last Post
Replies
9
Views
776
  • Last Post
Replies
21
Views
2K
  • Last Post
Replies
6
Views
1K
  • Last Post
Replies
5
Views
3K
Replies
1
Views
1K
Replies
3
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
1
Views
3K
Top