AIEEE Questions

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Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment.

Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. This removes material that will either float or readily settle out by gravity. It includes the physical processes of screening, comminution, grit removal, and sedimentation.

Secondary treatment removes the soluble organic matter that escapes primary treatment. It also removes more of the suspended solids. Removal is usually accomplished by biological processes in which microbes consume the organic impurities as food, converting them into carbon dioxide, water, and energy for their own growth and reproduction.

Tertiary treatment includes removal of nutrients such as phosphorus and nitrogen and practically all suspended and organic matter from waste water.

A perfectly inelastic demand curve is perfectly vertical either up or down in any way.

The kilowatt hour (kW⋅h) is a composite unit of energy equivalent to one kilowatt (1 kW) of power sustained for one hour.

One watt is equal to 1 J/s. One kilowatt hour is 3.6 megajoules.

We know that the circulatory system of our body is a loop. The Heart is the pump, the arteries and their smaller branches (arterioles) carry oxygen rich blood all through your body tissues from the heart and the veins and their smaller branches (venules) carry oxygen depleted blood and waste products back to the heart from all the body parts.

A tone in music is a sound that has definite pitch. Pitch is nothing but the relative highness or lowness of a sound.

In general, polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.
As water molecules are polar, polar molecules dissolves in water.