Solids,Liquids and Gases | Fact & information

Solids,Liquids and Gases

Matter can exist in different states. Solids, liquids, and gases are three common states of matter.

Solids have fixed shape and volume. Rocks and woods are solids. Liquids have indefinite shape, usually determined by the containers they till. Water and milk are examples of liquids. Gases have no shape. Examples of gases are oxygen and nitrogen gas.

Solids

Solid is the densest state of matter. Solids can be made of elements or compounds They can also be made of mixtures, or combinations of diiferent elements and compounds. Most rocks are mixtures of many elements and compounds. The molecules of solids are very tightly bound and packed into
regular shapes. There is a very little free space between the molecules and they cannot move.This gives solids their fixed shape and volume.

Liquids

Liquids are less dense than solids. The molecules of a liquid are not held together as strongly as in a solid. They can move around each other. This enables the liquids to flow. Liquids take the shape of the container they are held in unlike solids which keep their own shape. The molecules of a liquid often have a greater attraction for other substances than they have for each other. Therefore, they rise in narrow tubes above their own level. This action is called capillarity or capillary action. Plants draw water from the roots by capillary action.

Centre of gravity

The centre of gravity is an imaginary
point in an object where the total
weight of the body may be thought
to be concentrated. In other words, it
is the point within an object at which
gravity can be considered to act. It is
also called centre of mass. The mass of
a ring is thought to be concentrated at the centre of the ring (that is, in the air). The concept of centre of gravity is used in many applications. Engineers try hard to make sport cars as light as possible and then add weight to the bottom. In this way, the centre of mass of the car is nearer to the ground and thus, the car is
more stable.

Gravity on other celestial bodies

Gravity on the Sun is 28 times more than the gravity on the Earth. The gravity on the Moon is about one-sixth of the gravity on Earth. Due to the differences in gravity, the weight of an object will be different on different celestial bodies. For example, the weight of a person on the Moon is about one-sixth of that person’s weight on Earth.

Gravitational wave

Gravitational wave is a wave that is believed to travel at the speed of light and creates gravity. Some examples of systems that emit gravitational waves are binary star systems, where the two stars in the binary are white dwarfs, neutron stars or black holes.