What are lower and upper fixed point of a thermometer?
Question: What are upper and lower fixed points of a thermometer? Answer: The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point, or steam point, is the temperature of pure boiling water at normal atmospheric pressure.
What do you understand by lower fixed point define upper fixed point?
The lower fixed point is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point or steam point is the temperature of pure boiling water at normal atmospheric pressure.
What is used to determine the upper fixed point of a thermometer?
Those properties are; temperature of pure melting ice at normal atmospheric pressure and the temperature of pure boiling water at normal atmospheric pressure. The lower fixed point is determined by the temperature of pure melting ice and the upper fixed point is determined by temperature of pure boiling water.
How do upper fixed point calibrate in a thermometer?
To mark the upper fixed point, the thermometer is placed in a hypsometer containing water as shown in the figure. The bulb of the thermometer should be outside the water. When the mercury level becomes stationary at a temperature of steam, the level is marked, which represents the upper fixed point of the thermometer.
Why the expansion of the glass of the thermometer is ignored?
The change in the length of the glass tube with variation in temperature is so small that we can ignore that and concentrate on the expansion of the volume of liquid in the bulb. As this volume expands it forces the liquid up into the glass tube.
How do you find the lower fixed point of a thermometer?
The lower fixed point is determined by the temperature of pure melting ice and the upper fixed point is determined by temperature of pure boiling water. Once the Upper and lower points are fixed, we can now define a temperature scale. respectively.
What is the significance of upper and lower fixed points?
Hint: A temperature scale is defined by choosing two fixed points whose values are easily reproducible. In the case of the Celsius scale, the lower point is the melting point of pure ice at normal atmospheric pressure and the upper fixed point is the boiling point of pure water at normal atmospheric pressure (1atm).
What is the difference between upper and lower fixed points?
The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point, or steam point, is the temperature of pure boiling water at normal atmospheric pressure.
Why do upper fixed point calibrate in a thermometer?
What method is used to calibrate a thermometer?
ice-point method
The ice-point method is the most widely used method to calibrate a thermometer.
What is the lower fixed point of a thermometer?
The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure.
What makes a temperature mark on a thermometer?
Different atmospheric conditions will result in the thermometer showing different/wrong temperature readings. When the level indicated by the thermometric substance remains steady after some time, a mark will be made at that point. This mark will corresponds to the steam point (upper fixed point) and is assigned the value of 100 °C.
Which is the correct way to calibrate a thermometer?
To calibrate a thermometer is to mark a thermometer so that you can use it to measure temperature accurately. A fixed point is a standard degree of hotness or coldness such as the melting point of ice or boiling point of water.
Which is the lower fixed point of boiling water?
The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point, or steam point, is the temperature of pure boiling water at normal atmospheric pressure.