NTNUJAVA Virtual Physics Laboratory
Enjoy the fun of physics with simulations!
Backup site http://enjoy.phy.ntnu.edu.tw/ntnujava/
February 26, 2021, 11:37:47 pm *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
   Home   Help Search Login Register  
A man paints with his brains and not with his hands. ..."Michelangelo (1475-1564, Italian sculptor, painter, architect and poet)"
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 4569 times)
0 Members and 1 Guest are viewing this topic. Click to toggle author information(expand message area).
Hero Member
Offline Offline

Posts: 1796


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 465 times.)

* momentum1.png (105 KB, 1279x991 - viewed 440 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: 3086

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
A man paints with his brains and not with his hands. ..."Michelangelo (1475-1564, Italian sculptor, painter, architect and poet)"
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 13146 Last post October 10, 2007, 03:13:55 pm
by Fu-Kwun Hwang
Elastic Collision (1D)
Fu-Kwun Hwang 3 14819 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 6195 Last post April 05, 2010, 03:44:37 pm
by lookang
1 D collision carts Elastic and Inelastic Collision
ahmedelshfie 6 16335 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 5621 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 0.048 seconds with 22 queries.since 2011/06/15