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Title: Ejs Open Source Newton's Mountain Projectile Orbits Model java appletPost by: lookang on May 20, 2011, 10:44:32 pm
Ejs Open Source Newton Mountain Model java applet by Todd Timberlake remixed by lookang
Ejs Open Source Newton's Mountain Projectile Orbits Model java applet reference: http://www.compadre.org/osp/items/detail.cfm?ID=9391 http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=398.msg7167#msg7167 Title: Re: Ejs Open Source Newton Mountain Model java appletPost by: lookang on May 20, 2011, 10:48:30 pm
changes:
made sliders and fields conform to my design preference redo for SI units for closer to sg syllabus instead of arbitrary units originally made 22May2011 add earth picture add panel of x,y,vx,vy,ax,ay for calculating values to coincident with Earth data add trace instead of the older trail that can display older data rotate newton's diagram by 5 degree to coincident with x=0, instead of the older 0.1*R add time change to acceleration instead of force 24 May 2011 add multiple representation of versus time and distance from center of earth add menu for circular motion R,2R,3R and escape velocity at theta 0,45,90 26 May 2011 minor changes on menu list name R_earth instead of 6.38E06 as suggested by leongster made theta = blank add check box on the bottom panel for quick access as suggested by leongster. 07 june2011 added reference frame space and earth for earth to rotate if frame is space added a few geostationary orbits and non-geostationary remove newton mountain and replace with a rectangle to do newton mountain gif to make background transparent challenge: some problem detecting the boundary of earth solved double hitEarth (double x, double y) { if (!pass) { return x*x+y*y-R*R;} else { return 0;} } Title: Re: Ejs Open Source Newton's Mountain Projectile Orbits Model java appletPost by: lookang on May 23, 2011, 09:26:45 pm
question.
what is the velocity of the projectile if it is launch horizontally at the surface of the Earth? hint: use circular motion equation to find the v! enjoy! answer: 7920.05 m/s try it with the this customized with Earth data simulation :) Title: Re: Ejs Open Source Newton's Mountain Projectile Orbits Model java appletPost by: lookang on October 08, 2012, 05:32:34 pm
added http://weelookang.blogspot.sg/2011/05/ejs-open-source-newtons-mountain.html
Orbits round the EarthAn object projected horizontally near the Earth’s surface follows a parabolic trajectory. As the velocity of projection increases, there will be an occasion in which the trajectory follows the curvature of the Earth’s surface. If air resistance is negligible, the object will orbit round the Earth and will never meet the Earth’s surface.
Title: Re: Ejs Open Source Newton's Mountain Projectile Orbits Model java appletPost by: lookang on October 09, 2012, 03:19:54 pm
Question01
An earth satellite of mass 200 kg lost energy slowly through atmospheric resistance and fell from an orbit of radius 8.0 x 106 m to 7.8 x 106 m. Calculate the changes in the potential, kinetic and total energies of the satellite during this transition period. Answers: ( -2.57E8 J, 1.28E8 J, -1.28E8 J ) where E denotes x10 Solution: a) b) Assuming the orbits are in circular motion as it decays from to equation can be assumed to be valid to approximate this motion Thus, c) since check: This answer can also be verified from the formula relationship on page Newton's Mountain Projectile Orbits which is not intended to be memorized. Using the simulation:
Thus, ΔKE = 200(2.565X10^7 - 2.501X10^7) = 1.28X10^8 J ΔPE = 200(-5.131X10^7 - (-5.002X10^7)) = -2.58X10^8 J ΔTE = 1.28X10^8 + (-2.58X10^8) = 1.30X10^8 J where the slight difference is due to carry over error from the significant figures of the computer model. reference: http://commons.wikimedia.org/wiki/File:R_%3D_geo_Re_2012-10-08_1809.png#.7B.7Bint:filedesc.7D.7D Title: Re: Ejs Open Source Newton's Mountain Projectile Orbits Model java appletPost by: lookang on June 17, 2013, 07:34:00 am
taking the codes from fu-kwun hwang model here http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2083.0
i added the ability to fire and circular from this model space shuttle motion with impulse and added into the model above Ejs Open Source Newton's Mountain Projectile Orbits Model java applet http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2204.0 ! enjoy! http://weelookang.blogspot.sg/2011/05/ejs-open-source-newtons-mountain.html added ability to fire to add velocity to a achieve eclipse orbit and select circular to achieve circular orbit by applying impulse in directions to get velocity at the correct speed and direction, perpendicular to radius. this feature helps in the learning of energies change as satellite move from one circular orbit to another circular as requested by soo kok. https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejs_NewtonsMountainwee06.jar author: timberlake, lookang and fu-kwun hwang many thanks to prof fu-kwun hwang and his physics validated codes to help ordinary teachers make wonderful models for enhanced teaching and learning for the benefit of all humankind! licensed creative commons attribution. |