Write difference between absolute & secondary instrument.

Write difference between absolute & secondary instrument.
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1 Answer

Answer :

Absolute Instrument
Secondary Instrument
1. These give magnitude of quantity in terms physical constants of instruments 1. These give reading directly of the quantity at the time of measurement. 
2. Calibration is not required.
2. Calibration with absolute instruments is required time to time as per requirements.
3. Measurement is time consuming as of tedious calculations
3. Measurement is quick because of direct measurement. 
4. Very rarely used in practical applications.
4. Very widely used in practical applications.
5. Absolute instruments are used in laboratories as standardizing instruments.
5. Secondary instruments are used in everyday work.
6. Examples – Tangent Galvanometer, Absolute electrometer, and Raleigh current balance.
6. Examples – ammeter, voltmeter, amperehour meter, wattmeter etc.
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