Question

Concentrated load, at the centre. If the permissible stress ft = 75 kg/cm2 and fs= 10 kg/cm2 the safe load is (a) 3025 kg (b) 3050 kg (c) 3075 kg (d) 3100 kg answer: option c

Answer 1

Take higher stress equal to M/z and M = wl/4; z=bd^2/6 which comes to be 3072 so near answer is 3075.