Thursday, December 26, 2013

EJSS One Dimension Collision JS Model

updated 16 Nov2016

One Dimension Collision JS Model
One Dimension Collision JS Model
author: lookang
One Dimension Collision JS Model
author: lookang

The motion of a body of mass m and velocity v is described by a vector quantity known as momentum p where

$ p = mv$

When objects collide, whether trains, cars, billiard balls, shopping carts, or your foot and the sidewalk, the results can be complicated. Yet even in the most chaotic of collisions, as long as there are no net external forces acting on the colliding objects, one principle always holds and provides an excellent tool for understanding the collision. That principle is called the conservation of linear momentum which states that

The total momentum of a system remains constant provided that no external resultant force acts on the system.

For two bodies colliding linearly, it is written mathematically as a vector equation

Total initial momentum = total final momentum

$ m_{1}u_{1} + m_{2}u_{2} = m_{1}v_{1} + m_{2}v_{2} $

If external forces (such as friction) are ignored, the total momentum of two carts prior to a collision (left side of equation) is the same as the total momentum of the carts after the collision (right side of equation).

Collisions can be generally classified into these categories:

  • perfectly inelastic, e= 0
  • inelastic, e is a value from 0 to 1
  • perfectly elastic, e=1

There is also a concept of kinetic energy of a moving body is stated mathematically by the following equation:

$ KE_{1} = \frac{1}{2} m_{1}v_{1}^{2} $

Main Simulation View

The simulation has 2 collision carts on friction-less floor.
Explore the sliders allows varying the variables .

  •  mass of cart ONE, mass_1,  m1  in kg
  •  initial velocity of cart ONE,  u1 in m/s
  •  mass of cart TWO, mass_2,  m2  in kg
  •  initial velocity of cart TWO, u2  in m/s

Drop Down Menu

Allows for selecting what kind of collision is simulated.

A Perfectly elastic collision is defined as one in which both conservation of momentum and conservation of kinetic energy are observed
A Perfectly Inelastic collision is defined as one in which conservation of momentum is observed but the colliding carts stick together after collision with kinetic energy loss


Shows the Contact Force versus Time graph


Step Back
have their usual meaning.

A more powerful version of this simulation is available here
is available on the NTNU website
or here
collision cart
author: lookang, paco and engrg1
worksheets by
(lead) AJC:
(lead) RVHS:

Shout our thanks to the Ejs community namely, Francisco Esquembre , Fu-Kwun Hwang and Wolfgang Christian for their professional learning community support.