Ejs Open source Displacement & Velocity time graph for area & dx/dt java applet
Open source Ejs applet Displacement & Velocity time graph showing relationships of area & dx/dt

http://home.phy.ntnu.edu.tw/~lookang/EJS/EJS_4.0_080905/weexva3/weexva3.html old version
http://home.phy.ntnu.edu.tw/~lookang/EJS/EJS_4.0_080905/weexva4/weexva4.html old

adapted from Two dogs running (set up xi,vi, and a ) http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=188.msg810#msg810

Displacement & Velocity time graph applet showing relationships of area & dx/dt

Aims to show more clearly the ideas usually difficult for students

rate of change in displacement versus time at that time t = velocity at the same time.
Area of velocity versus time graph = distance traveled in Displacement time graph

/htdocs/ntnujava/ejsuser/14019/users/sgeducation/lookang/CatDogtRace_pkg/CatDogtRace.propertiesFull screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1540.8kB):double click downloaded file to run it. (62 times by 25 users) , Download EJS source (13 times by 10 users) View EJS source

reference: http://www.physicsclassroom.com/Class/1DKin/U1L1a.cfm
Kinematics is the science of describing the motion of objects using words, diagrams, numbers, graphs, and equations. Kinematics is a branch of mechanics. The goal of any study of kinematics is to develop sophisticated mental models that serve to describe (and ultimately, explain) the motion of real-world objects.

Concepts in the simulation http://www.physicsclassroom.com/Class/1DKin/U1L1c.cfm
Distance and Displacement
Distance and displacement are two quantities that may seem to mean the same thing yet have distinctly different definitions and meanings.
   * Distance is a scalar quantity that refers to "how much ground an object has covered" during its motion.
   * Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.

Speed is a scalar quantity that refers to "how fast an object is moving."
Velocity is a vector quantity that refers to "the rate at which an object changes its position."
Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.

The context of the simulation is based on a distance between -100 to 100 in the x axis direction.
at x=-100 is a house
at x = 100 is a tree.
there are 2 moving objects here cat 1 and dog 2 that are drag-gable in the motion diagram at the top.
there are 2 scientific graphs of x verus t and v versus t to allow for learning to translate between motion diagram to the scientific graphical representations
the sliders at the bottom allows learners to vary the initial displacement, initial velocity and uniform acceleration of the 2 objects.
the time slider can be vary after the simulation ends for learners to recap and make sense of the meaning of time in this particular simulation.
the play/pause, initialize and reset button are standard controls for the simulation.
the initialize button is especially useful for learners to plot 2 different cases of the simulations where the simulations remembers the earlier case and represent the plots in a darker color, for ease of comparison and trend generalization.