Step/C2/Introduction-to-STEP/English

Resources for "Introduction to STEP"

Introduction to STEP

Visual Cue	Narration
Slide 1	Hello. Welcome to this tutorial on how to use STEP
Slide 2 Slide 3 Slide 4 Slide 5	STEP is an interactive tool for Physics. Using this tool we can model the physical world by selecting objects and changing the parameters by which they interact. STEP is part of the KDE project and can be downloaded using the Synaptic Package Manager. In this tutorial on STEP, I have worked on Ubuntu version 10.04 LTS and STEP version 0.1.0 KDE 4.4.5
Slide 5. Open STEP	Now we will look at how to open STEP. Click on Applications, go down to Education scroll down to STEP. Click on it. This will open the STEP window.
STEP window Mouse over the palette, world scene and each of the panels Settings Tab and Adding Panels Tab to the World Panel Context information panel Properties Panel	The STEP window has three main components. On the left hand side, you will have the palette from which different objects can be added for the simulation, different interactions that can be added to the objects and various components through which the interactions can be added to the objects. In the middle, you have the world scene where the simulation can be built . On the right hand side, you have an area where different panels can be displayed. What you see displayed now are the properties panel and the world panel. You can add more panels for display here from the settings tab and by clicking on panels. If I add the Context Information, the context information panel will be added to this window. The world panel here gives information about all the objects and interactions in the simulation. It will also give us information about the various algorithms that are used to run the simulation. In this tutorial we will not be looking at the details of these algorithms. These may have to be learned using separate tutorials. The context information gives you specific information about each of the objects that are part of the simulation. The properties panel is where you can define the parameters of the objects that are part of the simulation and they will be displayed here when the simulation is being run. One more panel which can be added is that of the history panel which will give us information about how the simulation was built. In this simulation we will not add the history panel. We will look at how to build a simulation using STEP. Before that we will briefly summarize what we have looked at so far.
Slide 6 - 8	There are three main components - the palette, the world scene and the panels on the right, which are the world, the properties panel, the context information and the simulation history.
Slide 9 Slide 10 Slide 11 Slide 12	Now we will introduce a particle on the world scene and define the parameters of the particle in the properties panel. We will add forces which will add the conditions we want to simulate. And we will run the simulation. We will see how STEP works by the simulation of free fall of two objects.
STEP window	We will simulate the free fall of two disks. We click on Disk and click on the World Scene. I click on disk again and I click on the world scene. Disk 1 is at position (-1.21,1,36). Disk 2 is at (0.78, 1.53). These positions refer to the position of centre of mass of these disks. Now for this simulation, I want both these disks to be at the same vertical position above the x-axis. So I will change the y-co-ordinate of Disk 1 also to 1.53. Notice that the disk has moved up. Now I want to redefine the size of the second disk. I click on the box here and move it and the disk becomes smaller. The size can also be changed by clicking on the properties panel and changing the value of the radius here. I also want to redefine the mass of the second disk to be 1000 kg. Now we will add two weight forces, which are interactions, to these disks. Weight force is the acceleration due to gravity that will be experienced by a mass and has a value of 9.8 m/s2 and is a constant. I click on weight force. I click on weight force again. Weight force has been added on each of the disks. Now we are ready to run the simulation.
Simulation starts Properties panel	If you look at the world panel here, you will see that the disk 1, disk 2, weight force 1 and weight force 2 are all displayed here. Now we are ready to run the simulation. We stop the simulation. Now we will look at the properties of the disks. Disk 1 is at (-1.21, -4.134). Disk 2 is at (0.78,-4.134). They are both at the same y-co-ordinate position in the negative y-axis. The velocity of Disk 2 is -14.91 m/s and the velocity of disk 1 is also -14.91 m/s. This is an important result in the understanding in the study of gravitation. We know that these disks were of two different masses and sizes. Yet when they were subjected to free fall for the same amount of time, they traveled the same distance and reached the same final velocity. The final velocity of an object undergoing freefall is independent of the mass of the object.
File – Save-As dialog box	Now we will look at how to save the simulation. Click on File – Save As. We will call this as examplefreefall.step. All simulations under this application will be saved with the extension “.step”. Next time we want to demonstrate the simulation, we can simply open examplefreefall.step and simulate.
	Now we will look at an assignment to reinforce our understanding of STEP. Before we look at an assignment, we will see how and where to use STEP
Slide 13 Slide 14 Slide 15	STEP can be used to illustrate complex interactions in mechanics. After the theory has been introduced, the models can be built and simulated to reinforce understanding. This can be used as a supplement for syllabus at the college level.
Slide 16 Slide 17 Assignment simulation built	Now we will simulate a scenario when a ball is thrown upwards at a given angle to the horizontal. What is the path it takes and why would it follow such a path? The simulation when built will look like this. The blue arrow indicates the velocity of the object and the red arrow indicates the weight force. When you click on simulate, you will see that it quickly follows a parabolic path. Explain why it would take such a path.
Slide 18 Slide 19 Slide 20	I would like to acknowledge the Spoken Tutorial Project which is a part of a Talk to a Teacher Project. Supported by the National Mission on Education through ICT, MHRD, Government of India More information can be found here.
Slide 21	Thank you for joining me on this exploration of STEP. Hope you have fun exploring Physics using this tool. Thank you.

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