7. MEASUREMENT OF TEMPERATURE

7. MEASUREMENT OF TEMPERATURE
Key notes
1. Temperature is the measure of hotness or coldness of a body.
2. A thermometer makes uses of a physical property that changes with
temperature.
3. On the centigrade scale, the lower fixed point is the temperature of pure
melting ice (0 °C) and the upper fixed point is the temperature of steam above
boiling water at standard atmospheric pressure (100 °C).
4. On the absolute scale, temperature is measured in kelvins (K).
5. Absolute zero temperature is 0 K (-273 °C). This is theoretically the lowest
possible temperature.
6. The advantages of using mercury for liquid-in-glass thermometers are:
a) It does not stick to glass
b) It conducts heat well
c) It is easily visible
d) It expands uniformly
e) It has a wide range, from -40 °C to 355 °C
7. The range of a clinical thermometer is from 35 °C to 42 °C.
8. In a clinical thermometer, the construction prevents mercury thread from
flowing back into the bulb when the thermometer is removed from the
patient’s mouth.
9. A thermocouple thermometer is suitable for measuring high temperatures and
those that vary rapidly.
Formulas:
 0 °C = (273 + 0) K