What is the general name of :
(a) rigid form of matter ?
(b) fluid form of matter ?
Rigidity is the ability of a solid to maintain its form as it changes. That is, when an external force is applied to a solid substance, the form will remain unchanged. Fluidity is a characteristic that allows a molecule's particles to move around in space.
Rigid means 'unbending' or inflexible. A solid is a rigid form of matter so that it maintains its shape when subjected to outside force.
Fluids are substances that have a tendency to flow. A liquid is a fluid form of matter which occupies the space of the container. Liquids have a well-defined surface. Gas is a fluid form of matter which fills the whole container in which it is kept. Liquids and gases are known as fluids.
1. Rigid form of matter is a Solid:
2. Fluid form of matter is called 'liquid' or 'gas'.