## Tuesday, May 27, 2014

### EJSS Circular Motion Ferris Wheel Model

 EJSS Circular Motion Ferris Wheel Model http://weelookang.blogspot.sg/2014/05/ejss-circular-motion-ferris-wheel-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_ferrisWheelJSwee/ferrisWheelJSwee_Simulation.xhtml source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_ferrisWheelJSwee.zip authors: Mario Belloni, this version by lookang author of EJS 5: Paco.

## EJSS Circular Motion Ferris Wheel Model

this model uses the constant angular velocity to evolve the simulation

## Ordinary Differential Equation

$\frac{d \theta}{dt} = \omega$

## Position of Ferris Wheel Mass

the coordinates of the mass are spaced out by using

$x[i] = R sin(1+i) d \theta$

$y[i] = - R cos(1+i) d \theta$

$rot[i] = (1+i) d \theta$

where

$d \theta = \frac{2 \pi}{N_{1}}$

## General Description

This program simulates the effect of being on a Ferris Wheel. The simulation shows a wheel that can be varied in radius from 40 m (Ferris' original wheels) to 100 m, or about 10 meters larger than the current world record. In addition, the rotational speed of the wheel can be varied from -20 m/s to 20 m/s. By selecting the check-box, the free-body diagram can be shown.

This simulation is part of a collection of simulations related to amusement park physics. Additional simulations can be found on the OSP ComPADRE site.

Controls
Radius of the wheel (40 - 100 meters).
Speed: sets the speed of the Ferris wheel (-20 to 20 m/s).

Mario Belloni (mabelloni@davidson.edu) and now weelookang@gmail.com

## Changes made by lookang include

1. added velocity array to be display via check-box
4. made free body diagram to show weight and contact force while resultant force is a dotted line to illustrate the difference, actually FBD only has weight and contact force
5. added values to aid numerical calculations
6. made R = the outside hub to aid association of radius of circular motion made by carriage and man and woman
7. made time step to allow exactly 0 , 90 , 180 , 270, 360 degrees, previously was dt =0.02