4. A direct runoff hydrograph due to an isolated storm with an effective rainfall of 2 cm was trapezoidal in shape as shown in the below figure. The hydrograph corresponds to a catchment area (in sq. km) of
9. Which one of the following set of values give the minimum clear cover (in mm) for the main reinforcements in the slab, beam, column and footing, respectively, according to IS : 456-1978?
10. The centre of pressure of a liquid on a plane surface immersed vertically in a static body of liquid, always lies below the centroid of the surface area, because
Options
A. in liquids the pressure acting is same in-all directions
B. there is no shear stress in liquids at rest
C. the liquid pressure is constant over depth
D. the liquid pressure increases linearly with depth