[url=http://mfcosmos.com/archives/15059][color=#1e84cc]MATHS AND PHYSICS... WORLD >>>>>>>>>>>>>>>[/color][/url][br][color=#1551b5]How moves the yoyo exerting force through the thread ... up or down ... and why ...[br]...with choice of two [b]"moving cameras"[/b]...[/color]