Plate 3A Choreography  (Bending & Flexing)	3B Indian Choreography	3C Indian Classical Dance

(Source: http://www.google.co.in/search?hl=en&q=Rhythmic+Dance&bav=on.2,or.r_gc.r_pw.r_qf.&biw=
1328&bih=574&um=1&ie=UTF8&tbm=isch&source=og&sa=N&tab=wi&ei=yro1UKakOc3qrQeev4CYCA#
um=1&hl=en&tbm=isch&sa=1&q=Rhythmic+Choreograph+Dance&oq=Rhythmic+Choreograph+Dance
&gs_l=img.12...278565.284028.5.286702.11.11.0.0.0.0.0.0..0.0.cghsbq..0.0...1.J-50wWqVahs&pbx=1&
bav=on.2,or.r_gc.r_pw.r_qf.&fp=8ee0ab7085cd0400&biw=1328&bih=574 ; Aug. 23, 2012)

While the term bending is clear when we are talking about knee-joint, it is somehow less clear when we talk about man-made objects, suggesting more a bend in a coat hanger wire that a mechanical equivalent of a knee joint. But just a flexing a knee changes the angular relationship between two rigid members (plate 2C), similar transformations must be accommodated in such applications as lifting the boom of a crane (plate 4B), raising a drawbridge (plate 4C) or installing a section of a metal conduit.

Plate 4 A Rhythmic Dance	4B Crane Bending	4D Draw Bridge Bending