The minimum change in the measured variable which produces an effective response of the instrument is known as?

Option 3 : resolution

The minimum change in the measured variable which produces an effective response of the instrument is known as resolution.

Concept:

The static performance parameters of the instruments are:

1. Accuracy
2. Precision
3. Resolution
4. Threshold
5. Static sensitivity
6. Linearity
7. Hysteresis
8. Backlash
9. Dead band
10. Drift

• Accuracy: It is the closeness with which an instrument reading approaches the true value of the quantity being measured. It means conformity to truth.
• Precision: It is defined as the ability of the instrument to reproduce a certain set of readings within a given accuracy
• Drift: It is defined as the variation of output for a given input caused due to change in the sensitivity of the instrument to certain interfering input like temperature changes, component instability, etc.
• Resolution: It is defined as the smallest increment in the measured value that can be detected with certainty by the instrument.
• Threshold: It is defined as the minimum value of input below which no output can be detected.
• Static sensitivity: It is defined as the ratio of the magnitude of response to the magnitude of the quantity being measured.
• Linearity: It represents the output of the instrument which is a linear function of the input.
• Hysteresis: It is defined as the magnitude of error caused in the output for a given value of input when this value is approached from opposite directions, i.e. from ascending order and then descending order.
• Dead band: It is defined as the largest change of the measurand to which the instrument does not respond.
• Backlash: It is defined as the maximum distance or angle through which any part of the mechanical system may be moved in one direction without causing motion of the next part.