A three-point bending test is performed on a glass specimen having a rectangular cross section of height d = 5 mm (0.2 in.) and width b = 10 mm (0.4 in.); the distance between support points is 45 mm (1.75 in.).
(a) Compute the flexural strength if the load at fracture is 290 N (65 lbf).
(b) The point of maximum deflection Δy occurs at the center of the specimen and is described by

where E is the modulus of elasticity and I is the cross-sectional moment of inertia. Compute Δy at a load of 266 N (60 lbf).

FL 48EI