A simply supported beam of span ‘L’ carries a concentrated load ‘W’ at mid-span. If the width ‘b’ of the beam is constant and its depth is varying through out the span, then what would be its mid-span depth when design stress is ‘f’?

A

$$\sqrt{\frac{6WL}{bf}}$$

B

$$\frac{6WL}{bf}$$

C

$$\sqrt{\frac{3WL}{2bf}}$$

D

$$\frac{3WL}{2bf}$$