WEIGHING BALANCE CALIBRATION
Truely speaking weiging balance means balance the two weights (mass), thus determine the mass of an object by comparing with a known mass. This utilises two pans suspended on a beam and having a fulcrum at the center of the beam. To determine the mass of an object, we need to have the same amount of mass on the opposite pan which is impractical in most of the situation. With the tecnological developement, various types of weighing balances and weighing scales have beed designed and in use to dtermine the exact mass (conventional mass) of the object. Weighing scales measure the weight of the object which is the function of gravitational force of the earth. This can be understood with the below given expression. Weight is a gravitational force and
F= m.g
where ‘F’ is the force, ‘m’ is mass and ‘g’ is acceleration due to gravity.
For an object in free fall, where gravity is the only force acting on it, then the expression for weight follows from Newton’s second law
W = F = mg applies at all times, even when the object is not accelerating.
Mass of an object can not change but the weight will change depending upon the value of gravitational force, g. On earth, value of g is maximum on the surface. It means when we go up, g value will decrease and hence weight of the body will also decrease. Similarly, if we go inside (below) the earth, g value will decrease and hence weight of the body will decrease. ‘g’ value decreases twice below the earth as compared to the same distance above the earth.
Though ‘g’ value is maximum on the surface of the earth, it is not same at all the location and hence weight of a body is not same at all the location on the surface of the earth. Reason for this is that the earth is not spherical round.
Calibration of weighing balance (weiging scale) is done at the place where is intended to be used due to above reason.
Calibration of electronic balance involves determination of
A.Linearity
B.Repeatability
C.Eccentricity
D.Hysteresis
Our ICS Technology Mass laboratory has requisit infrastructure and expertise to calibrate weiging balance/scale with NABL accreditation.
|