Question

Q3. What do you understand by upper fixed point and lower fixed point?
04. Why is mercury and not water used in thermometers?
05. Name the scales used to measure temperature.
06. Give reasons for the following
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Answer 1

Answer: 3)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.

4)Mercury is the only one in liquid state at room temperature. It's used in thermometers because it has high coefficient of expansion. Hence, the slightest change in temperature is notable when it's used in a thermometer. It also has a high boiling point which makes it very suitable to measure higher temperatures

5)Three scales are commonly used for measuring temperature. The Celsius and Fahrenheit scales are the most common. The Kelvin scale is primarily used in scientific experiments.

6) i dont know

Explanation: