Quiz: Civil Engineering
Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes
Q1. Separation of water or water sand cement from a freshly mixed concrete is known as
Q2. Admixtures which cause early setting and hardening of concrete are called:
(c) Air entraining agents
(d) Workability admixture
Q3. Inside pressure in a hollow soap bubble in the air is: (where d is the diameter of the bubble)
Q4. If the volume of a liquid weighing 3000 kg is 4 cubic metres, 0.75 is its
(a) Specific weight
(a) Specific mass
(c) Specific gravity
(d) None of these
Q5. The property of steam function ψ is:
(a) ψ is constant everywhere on any stream line
(a) The flow around any path in the fluid is zero for continuous flow
(c) The velocity vector may be found by differentiating the stream function
(d) All the above.
Q6. A line which joins subsidiary stations on the main line is called _____
(a) Tie line
(b) Survey lines
(c) Base lines
(d) Check lines
Sol. Bleeding→ Separation of water from a freshly mixed concrete is called bleeding.
Segregation→ Separation of coarse aggregates from mortar during transportation is called segregation. Due to segregation voids in concrete increased and strength of concrete decreased.
Sol. Accelerators are the chemicals used to accelerate the setting and hardening of concrete. Calcium chloride is used an accelerator that increase the rate of hydration.
Sol. → The pressure inside in a hollow soap bubble in the air is 8σ/d.
→ The pressure inside in water droplet is 4σ/d.
→ The pressure inside in liquid jet is 2σ/d.
Where, d = diameter
σ= Surface tension
Weight of liquid (W) = 3000 kg
Volume of liquid (V) = 4 m³
Density of liquid (ρ) =W/V=3000/4 = 750 kg/m³
Specific gravity (G) = (Density of liquid (ρ))/(Density of water(ρ_w ) )
Sol. The properties of stream function are-
→ Ψ is constant everywhere on any stream line.
→ The rate of change of Ψ with distance in an arbitrary direction, is proportional to the component of velocity normal to that direction.
→ The flow around any path in the fluid is zero for continuous flow.
→ The velocity vector may be found by differentiating the stream function.
Sol. Tie lines → A line which joins subsidiary stations on the main line. These lines are helpful for locating the inner details of the area.