1.
Measurement
Estimation
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2.
Measurement of Weight, distance, period is sometimes
estimated or sometimes accurately done.
While measuring vegetables, food grains, shopkeeper
sometimes give a bit more of vegetable or food grain.
Whereas gold, silver, ingredients of medicines are measured
accurately.
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3.
While measuring long distance places or spots, a little more or
less variation in distance is usually observed.
But for preparing and fitting the spare parts of any machine ,
distance has to be accurate.
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4.
There might be 10-15 minutes delay here or there for
starting of any program. But the timing for launch of rocket
or scientific tests has to be accurate.
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5.
This means some measurements can be estimated but some
measurements needs to be accurate.
Valuable, important, things used in small quantity, proportion had
to be measured accurately.
Depending on the purpose of measurement, how accurate it is
required gets decided.
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6.
Earlier accurate measuring instruments were not available.
Because of advancement in technology, mass, distance and time
can be measured accurately.
Composition of important chemicals, small parts used in computer,
T.V, measurement of time in milliseconds required for various
game’s competition has to be measured accurately.
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7.
Even though for measuring accuracy there are digital balance, stopwatch
available but still mistakes might happen due to some reasons.
Lack of zero position, positioning zero at wrong place, inaccuracy while
observing , negligence on the part of observer, fault in the instrument, due to
such reasons measurements can be inaccurate.
Limitations of the instrument and negligence while handling the instrument are
the reasons for inaccuracy of results while measurement.
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8.
To avoid measuring things inaccurately and cheating
the customers, government had made some laws. If the
laws are not obeyed then compliant can be registered
in consumer court.
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9.
For measuring weight , rules are as under.
Seller has to use certified measurements.
Balance has to be stable at one point.
The rod of balance should swing easily around vertical axis.
On the rod there should be certified mark of weight
measuring department.
Every weight should have a hole in the centre and that hole
should be filled with lead. That lead should have the
stamp/mark of weight measuring department.
Such weight is a certified weight. Weight measurement
should be of metal only.
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