NTNUJAVA Virtual Physics Laboratory
Enjoy the fun of physics with simulations!
Backup site http://enjoy.phy.ntnu.edu.tw/ntnujava/
November 16, 2018, 09:23:28 am *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
   Home   Help Search Login Register  
Wisdom is to bring the best out of our students. ...Wisdom
Google Bookmarks Yahoo My Web MSN Live Netscape Del.icio.us FURL Stumble Upon Delirious Ask FaceBook

Pages: [1]   Go Down
Author Topic: Physics of collision showing forces at event for 1 dimension  (Read 3858 times)
0 Members and 1 Guest are viewing this topic. Click to toggle author information(expand message area).
Hero Member
Offline Offline

Posts: 1787


Embed this message
on: March 13, 2012, 02:01:30 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

Dear Prof Hwang,

Ease of changing your own code:
This model is very similar to my own collision model,  i wish to study your implementation of contact forces inside your model.

My intent:

i am trying to change my own collision model http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=831.0 to include accurately the forces during impact.


my implementation is flawed with this in-correct physics and i wish to get your help on this matter.
notice in the attachment pictures
t = 0 to t = t_collision = 0.295, momentum1 = m1*u1 = 8, Momentum2 = m2*u2, contact force = 0
t = t_collision+ dt = 0.30, momentum1 = m1*v1 = -4 , Momentum2 =not shown, contact force = maximum = -800
t = t_collision+ 2*dt to t_end of simulation, momentum1 = m1*v1 = -4 , Momentum2 = m2*v2 = not shown, contact force = 0
notice the physics (RED) is wrong, can you help make your model show contact forces correctly? I can study your model to learn Smiley

My Plan A:
my plan is to split the event handler into 2 parts,
t = 0 to t = t_collision, momentum1 = m1*u1 = , Momentum2 = m2*u2, contact force = 0
t = t_collision+ dt, momentum1 = (some midpoint to be calculated ) , Momentum2 = (some midpoint to be calculated), contact force = maximum
t = t_collision+ 2*dt to t_end of simulation, momentum1 = m1*v1, Momentum2 = m2*v2, contact force = 0
but i don't' know how to start the solution Smiley

Possible Plan B:
could be squeezing at peak force to show at t = t_collision+ dt/2
but i don't' know how to start the solution Smiley Is there a way to create a dt/2 inside the event?

My request:

can you demonstrate what you would do in your own model here http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1435.msg8223#msg8223
You can implement the inclusion of contact forces whichever way you feel is correct physics, i will try to understand it!

* forces1.png (103.5 KB, 1277x990 - viewed 383 times.)

* momentum1.png (105 KB, 1279x991 - viewed 358 times.)

*** There are 1 more attached files. You need to login to acces it!
« Last Edit: March 13, 2012, 02:18:23 pm by lookang » Logged
Fu-Kwun Hwang
Hero Member
Offline Offline

Posts: 3080

Embed this message
Reply #1 on: March 13, 2012, 10:41:18 pm » posted from:Taipei,T'ai-pei,Taiwan

There is no way to find the force between two objects (when they collide with each other) without further information.
e.g. model for interaction between object when they collide.

You are welcomed to check out Simulate 1D collision with a virtual spring. A spring is used to model the collision process(spring constant depends on the softness of both objects).
Pages: [1]   Go Up
Wisdom is to bring the best out of our students. ...Wisdom
Jump to:  

Related Topics
Subject Started by Replies Views Last post
collision between twp particles in one dimension(along a line)
Examples for beginner who want to learn EJS
Fu-Kwun Hwang 0 12068 Last post October 10, 2007, 03:13:55 pm
by Fu-Kwun Hwang
Elastic Collision (1D)
Fu-Kwun Hwang 3 13270 Last post April 13, 2013, 04:54:31 pm
by Fu-Kwun Hwang
Electric Field and Potential in One Dimension
Simulations from other web sites
ahmedelshfie 3 5457 Last post April 05, 2010, 03:44:37 pm
by lookang
1 D collision carts Elastic and Inelastic Collision
ahmedelshfie 6 12833 Last post April 27, 2010, 02:16:18 am
by ahmedelshfie
how do you calculate forces in a collision?
Question related to Physics or physics related simulation
Bluzkin 1 4987 Last post November 24, 2010, 09:51:48 pm
by Fu-Kwun Hwang
Powered by MySQL Powered by PHP Powered by SMF 1.1.13 | SMF © 2006-2011, Simple Machines LLC Valid XHTML 1.0! Valid CSS!
Page created in 0.31 seconds with 23 queries.since 2011/06/15