One of the following statements is true with regards to bodies that float or are submerged in liquids :
Options
A. For a body wholly submerged in a liquid the stability is ensured if the centre of buoyancy is below the centre of gravity of the body
B. For a body floating in a liquid the stability is ensured if the centre of buoyancy is below the centre of gravity of the body
C. For a body floating in a liquid the stability is ensured if the centre of buoyancy and the centre of gravity, regardless of the relative positions of the centre of buoyancy and gravity
D. For a body floating in a liquid the stability is ensured if the centre of buoyancy is below the centre of gravity and the metacentre is above both the centres of gravity and buoyancy.
Correct Answer
For a body floating in a liquid the stability is ensured if the centre of buoyancy is below the centre of gravity and the metacentre is above both the centres of gravity and buoyancy.
3. The downstream end of a long prismatic channel of mild slope, ends in a pool created by a dam. The resulting non-uniform water surface profile can be described as one of the following :
Options
A. M3 profile ending in a hydraulic jump
B. M1 profile that lies above normal depth line
C. M2 profile that lies between critical and normal depth lines
D. M3 profile that lies between critical and normal depth lines
Correct Answer: M3 profile that lies between critical and normal depth lines
4. A prestressed concrete rectangular beam of size 300 mm x 900 mm is prestressed with an initial prestressing force of 700 kN at an eccentricity of 350 mm at midspan. Stress at top of the beam due to prestress alone, in N/mm2 is
8. The ultimate bearing capacity of a soil is 300 kN/m2. The depth of foundation is 1 m and unit weight of soil is 20 kN/m3. Choosing a factor of safety of 2.5, the net safe bearing cacpacity is
9. The return period for the annual maximum flood of a given magnitude is 8 years. The probability that this flood magnitude will be exceeded once during the next 5 years is