The figure shows two fluids held by a hinged gate. The atmospheric pressure is Pa = 100 kPa. The moment per unit width about the base of the hinge is ____________ kNm/m. (Rounded off to one decimal place)
Take the acceleration due to gravity to be g = 9.8 m/s2.
A uniform wooden rod (specific gravity = 0.6, diameter = 4 cm and length = 8 m) is immersed in the water and is hinged without friction at point A on the waterline as shown in the figure. A solid spherical ball made of lead (specific gravity = 11.4) is attached to the free end of the rod to keep the assembly in static equilibrium inside the water. For simplicity, assume that the radius of the ball is much smaller than the length of the rod.
Assume density of water = 103 kg/m3 and π = 3.14.
Radius of the ball is _______ cm (round off to 2 decimal places).
The specific gravity of oil is $$0.7$$ and density of water is $$1000$$ $$kg/{m^3}.$$
Acceleration due to gravity $$g = 10\,m/{s^2}$$