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How Interactive Physics Works


Interactive Physics is a computer program that allows the user to model real-world physical situations. Solid bodies of varying shapes and sizes can be made to move or collide with different velocities and accelerations, and properties of the objects such as mass, elasticity, and friction can be changed.

These bodies can also be constrained together so that balls can be made to move in circles, blocks can be slid across a frictionless table, or joints can be created which allows objects to move in fixed paths.

Interactive Physics was used to model the frictionless sliding of a non-rotating ball on a smooth loop-the-loop track. This was done by first creating an outline of the loop using imaginary points. The center of the circle was at (0,0), and eight points were created equidistant from each other around the circle, each at a distance of 0.137 m (the radius of the actual loop).



Then, a point was created to mark the position of the starting height h of the ball. This point was placed 0.206 m from the bottom of the loop. Several sets of points were placed to the right of the loop and in line with the bottom of the loop. At this point, an outline of the loop had been formed from imaginary points. For explanation of how we calculated our initial height shown below, click here to go to our theory.




A ball of radius 0.120 m and mass 0.066 kg was made and was centered at the point placed 0.206 m above the bottom of the loop. Then, the curved slot constraint in the IP toolbar was used to create the imaginary frictionless track that the ball would later slide on. By selecting the curved slot constraint and clicking on each of the imaginary points in sequence (as shown below), a loop-the-loop track was created. The track was ended at the last point by double-clicking, and the end product is shown in our Interactive Physics .avi file.


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Back to Experimental Setup

Table of Contents





Table of Contents




How Interactive Physics Works

Our Materials List

The Experimental Setup

How Our Data Was Analyzed

Interpretation of Data