Nonuniform forces Imaginary plane Uniform forces F N=F Uniform Internal Forces ONA=FA External forces Internal forces and stresses Stress on a plane: internal forces acting on unit area of the given plane within the considering body
Uniform forces Nonuniform forces External forces Imaginary plane Uniform Internal Forces a b a F F F N=F =N/A=F/A Internal forces and stresses Stress on a plane: internal forces acting on unit area of the given plane within the considering body. x
External forces △P m △E △P Internal △F forces area p stress △Pcp limar D △F->0 △FdF
p dF dp F P F = = → lim 0 m Interna l forc e area F P P— F— External forces Internal forces area stress