SSC JE Civil Engineering 2018 Set 2 Solved Paper

For beams of uniform strength, if depth is constant, then width is directly proportional to bending moment.
Max bending moment; M=W.z (equation 1)
Bending equation is: M/I = F/y = E/R
M = F. (I/y) or F.Z = F. (bd‌2 /6) (equation 2)
Now, equate equation 1 and 2 gives;
F. (bd‌2 /6) = W.z
b = {6W.z/Fd‌2 } or [6M/Fd‌2 ]
Hence width is directly proportional to bending moment.