MT-1620 al.2002 Sum forces and moments dF F+F+dx+p, dx d1 ds, dw d S-+s+adx dx|=0 ax This leaves (dx) dF dsdw dw dx+p, dx S- ldx+HOT=0 dx dF → p S 17-1) ax new term Paul A Lagace @2001 Unit 17-4MIT - 16.20 Fall, 2002 Sum forces and moments: + • ∑Fx = 0 : dF − F F + + dx + px dx dx 2 − S dw + S + dS dx  dw + d w dx = 0 dx  dx   dx d x2  This leaves: 2 dF  d S dw S dw  dx + px dx +  + 2  dx + H O T. = 0 (dx)2 .. dx  d x dx dx  ⇒ dF dx p d dx S dw dx = − x    −  (17-1) new term Paul A. Lagace © 2001 Unit 17 - 4