Solids.

Solids are rigid substances which have definite volume and posses definit shape.

Physical Classification of Matter.

On the basis of rigidity, volume, and shape, all matter can be grouped into Solids, Liquids and Gases.

Classification of Matter.

The entire universe is made up of matter and energy. Matter may be defined as any thing which occupies space and has mass. In fact all objects in the universe are composed of matter. Some examples of matter are air, watter, mountains, planets, plants, animals and man. Since matter exists in countless forms, its study can be simplified by dividing it into different classes depending upon its properties.

Special notes on the uses of SI units-7

The degree sign to be omitted when the kelvin scale is employed. For example, 273 K

Special notes on the uses of SI units-6

Digits should be grouped in three about decimal point in order tofacilitate the reading of long numbers. Commas should not be used to space digits in numbers. For example, 12345678.12345 and not 1,23,45,678.123,45.

Special notes on the use of SI units -5

Symbols for units are the same in the plural and in the singular forms. For example, 10 kilograms is written as 10 kg and not as 10 kgs. 30 grams is written as 30 gm and not 3 gms.

Special notes on the uses of SI units.-4

According to the conventions, symbols are not to be followed by full stop. For example, km not km.