6. If At is the gross area of steel in tension, d is the effective depth of the beam and y is the depth of the centre of gravity of the resultant compression, the moment of resistance M of the beam, is given by
8. An open-ended cylinder of radius r and thickness t is subjected to internal pressure p. The Young's modulus for the material is E and Poisson's ratio is ?. The longitudinal strain is
9. A reinforced concrete cantilever beam is 3.6 m long, 25 cm wide and has its lever arm 40 cm. It carries a load of 1200 kg at its free end and vertical stirrups can carry 1800 kg. Assuming concrete to carry one-third of the diagonal tension and ignoring the weight of the beam, the number of shear stirrups required, is