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I'm wondering the difference between the 'least count' and the 'smallest division' of an instrument. Can you explain that for me, plz?

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It is the difference between continuous and discreet.

A least count, for example in a geiger counter, would be an integer number=1 since one can detect single hits.

A smallest division will be given by a real number. In voltmeters for example the division is continuous because the potential is a continuous quantity.

Both should be accompanied by a +/- error.

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Can you give me easier examples? And what's the definitions of least count and smallest division? – QED Mar 2 '13 at 0:29
did you look at the voltmeter? I gave a link, which is high lighted. On the face of the voltmeter you see a needle that will move when the two contacts measure a voltage. the scale is calibrated from 0 to a high value, but there exists a smallest reading/division corresponding to the width of the needle. This also reflects that voltage is a continuous measure, so there is a one to one correspondence of needle position to voltage with an error given by the smallest discrimination. – anna v Mar 2 '13 at 4:57
When one measures discreet variables, people or ships or sheep the variables are discreet. Any counter measuring this will have as minimum accuracy 1 and even if the counter's indicator has a first reading at 10, the measurement will be of a discreet variable, and it will be a "least count" because one is counting in integers. – anna v Mar 2 '13 at 5:00

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