Explanation at http://xmdemo.wordpress.com/068

www.xmphysics.com is a treasure cove of original lectures, tutorials, physics demonstrations, applets, comics, tenyearseries solutions, for every student preparing for the GCE Alevel (preuniversity) physics examinations.

Created by Mr Chua Kah Hean, a oneman crusader for equal access to top quality education resources.

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