# Can anyone please explain me the concepts of the above topics??? Waiting anxiously..............

112 Points
14 years ago

Hi,

Linear momentum is a vector quantity, since it has a direction as well as a magnitude. Angular momentum is a pseudovector quantity because it gains an additional sign flip under an improper rotation. The total momentum of any group of objects remains the same unless outside forces act on the objects (law of conservation of momentum).

Collision is an isolated event in which two or more moving bodies (colliding bodies) exert relatively strong forces on each other for a relatively short time.Collisions involve forces (there is a change in velocity). Collisions can be elastic, meaning they conserve energy and momentum, inelastic, meaning they conserve momentum but not energy, or totally inelastic (or plastic), meaning they conserve momentum and the two objects stick together. The magnitude of the velocity difference at impact is called the closing speed. The field of dynamics is concerned with moving and colliding objects.

Two types of collision
A perfectly elastic collision is defined as one in which there is no loss of kinetic energy in the collision. An inelastic collision is one in which part of the kinetic energy is changed to some other form of energy in the collision.

Center of mass of a system of particles is a specific point where, for many purposes, the system behaves as if its mass were concentrated there. The center of mass is a function only of the positions and masses of the particles that compose the system. In the case of a rigid body, the position of its center of mass is fixed in relation to the object (but not necessarily in contact with it).