Temperature measures heat. Along with a measure of ‘thermal mass’ of a body it gives an indication of total thermodynamics energy that body contains. Various types of scales for the comparison of temperature that the most important part is their corresponding values for melting ice and boiling water as well as the common reference temperature.
To compare the time constant of different type of measuring devices with reference mercury filled thermometer and understand relationship between resistance and temperature, and main difference between resistance thermometer and thermistor. Also, understand the concept of resistance thermometer and thermistor using PT100 and NTC probes.
We have various types of thermometers to measure heat. In this experiment, we use several types of thermometers such as Type K, Pt100, Bi-metallic, Mercury, vapour pressure and spirit type. Different types of thermometer requires different methods to measure heat. Namely, mercury type of thermometer that is very fragile and contains a capillary tube with bulbous end that when heat is gained, the mercury expands in the tube and a column is pushed along the tube bore. The vapour pressure thermometer in the other hand, contains a metal bulb that is partially filled with fluid that is connected at the sensing element of Bourdon gauge. This type of thermometer is only suitable for operation over short ranges temperatures and suffers lack of sensitivity at low reading. Bi-metallic type of thermometer consists of two thin metal strips with different coefficients of linear expressions and they are mechanically fastened together and the result shows when a strip bends significantly when heated
- Type K thermocouple
- Pt100 thermocouple
- mV meter
- Main switch 240V AC
- Heater switch
- Blower switch and speed controller
- Pt100 temperature meter
- Type K temperature meter
- Bi-metallic thermometer
- Hot water pot
- Vacuum Flask
- Vapour compression thermometer
- Whirling psychrometer
- Thermistor temperature meter
- Mercury filled thermometer
- Spirit-filled thermometer
- ELCLB / MCB
- The 3 pin plug was plugged in to 220V AC main power supply and the power supply was switched on.
- MCB / ELCB was made sure to switch on.
- The main power supply was switched on for the apparatus.
- The water poured into the hot pot. The water level must at least half of the pot.
- The small cap on top of the water pot was removed from the hot water pot.
- The desirable temperature measurement device was chosen, and placed into the hot water pot. Mercury Filled Thermometer used as reference temperature point.
- The initial temperature reading was stated and recorded in the table.
- The water heater was turned on and the hot water pot was made sure to turn on.
- For every 2 minutes interval, the temperature reading was stated and recorded into the table.
- Step 9 was repeated until the water boiled.
- The experiment was repeated with different type of temperature measuring devices.
- Data, Observation and Result
- Thermometer (°C)
- Time (mins) Mercury Type Bi- metallic Pt100 Type K Spirit Type Vapour Pressure
0 49 38 93.9 41.4 34 45
2 52 39 68.3 44.1 34 47
4 60 47 77.5 52.3 50 55
6 78 57 89.7 63.9 60 66
8 90 66 100.6 73.3 71 78
- Analysis and Discussion
In this experiment, I learnt the uses and methods of using different type of thermometers to measure heat at certain amount of time and also understand the relationships between the thermometer readings and time given.