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प्रश्न
Answer the following question.
How a thermometer is calibrated?
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उत्तर
- For the calibration of a thermometer, a standard temperature interval is selected between two easily reproducible fixed temperatures.
- The fact that substances change state from solid to liquid to a gas at fixed temperatures is used to define reference temperature called a fixed point.
- The two fixed temperatures selected for this purpose are the melting point of ice or the freezing point of water and the boiling point of water.
- This standard temperature interval is divided into sub-intervals by utilizing some physical property that changes with temperature.
- Each sub-interval is called as a degree of temperature. Thus, an empirical scale for temperature is set up.
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संबंधित प्रश्न
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| Triple-point of water | 1.250 × 105 Pa | 0.200 × 105 Pa |
| Normal melting point of sulphur | 1.797 × 105 Pa | 0.287 × 105 Pa |
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| Steel |
| Aluminium |
| Steel |
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