Current Attempt in Progress

A three$-$point bending test is performed on a glass specimen having a rectangular cross section of height $4\mathrm{.}2$ mm and width $10\mathrm{.}9$ mm ; the distance between support points is $49$ mm $.$

$($a$)$ Calculate the flexural strength $($in MPa$)$ if the load at fracture is $298$ N $.$

${}_{fs}=,$MPa

$($b$)$ The point of maximum deflection $y$ occurs at the center of the specimen and is described by the expression

$y=\frac{F{L}^3}{48EI}$

where $E$ is the modulus of elasticity and I the cross$-$sectional moment of inertia. Calculate $y$ of $251$ N $.$ Assume that the elastic modulus for the glass is $68$ GPa $.$

$y=$