Mass And Weight

Mass

• Mass is the amount of matter in a given object..

• Anything made up of matter has mass. It will be same every where..

• The SI unit of mass is the kilogram (kg).

Common Balance is usedto

measure the mass.

• The weight of an object is usually taken to be the force on the object due to gravity..

• Is the product of the mass m of the object and the magnitude of the gravitational acceleration “g”

W = mg

• The unit of measurement for weight is that of force, which is the newton(N)..

Weight

A spring scale measures the weight of an object.

Centre Of Gravity

• Center of gravity is an imaginary balancing point where the body weight can be assumed to be concentrated and equally distributed.

• Its symbol is COG or CG..

• It is the point of exact center, around which the body may rotate freely in all directions. It can also be called center of mass..

• The center of gravity can be located within or outside the body depending on the body's configuration and position.

• It is inside an object when the object is uniform and outside the object when it is not uniform.

States Of Equilibrium

There are three states of equilibrium:

Stable equilibrium

Unstable equilibrium

Neutral equilibrium

Stable equilibrium A state in which a body tends to return

to its original position after being disturbed.

Unstable equilibriumA state of equilibrium in which a small

disturbance will produce a large change.

Neutral equilibriumA body so placed that when moved slighty

it neither tends to return to its former position not depart more widely from it..