Task One
In this task, three methods of measuring temperature have been summarized. The fundamental physics and equations underlying the measurement, a figure supporting the description, a description of the range, accuracy and precision, advantages and disadvantages, and how these devices produce digital signals will be discussed in this task.
Vapor Pressure Thermometers
The system of a Vapor Pressure Thermometers contains both vapor and liquid but it is still considered as a type of gas filled instrument. A bulb is used to store the mixture of both phases, and it is this bulb that is suspended into the medium whose temperature needs to be measured. This bulb is connected to a bourdon tube which measures the vapor pressure of the liquid inside the bulb. The basic physics behind this thermometer is that exposing the bulb to higher temperatures increases the vapor pressure of the liquid inside the bulb making the bourdon tube needle to depict a higher pressure reading and vice-versa. The bourdon tube readings can be calibrated and converted to the temperature readings using equations of state.1
The equations of states such as the ideal gas can be used to relate temperature, pressure and the number of moles of gas present in the bulb. In this thermometer the number of moles of gas inside the bulb remains constant leaving only two variables which are temperature and pressure. The correlation between the pressure and temperature can be made using the ideal gas equation. In the ideal gas equation, the temperature of the gas is directly proportional to the vapor pressure of gas inside the bulb. However, this relation might not be linear because all gases do not obey the ideal gas law. In the...
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...t. The signal conversion is fairly easy in thermocouple since a voltage signal is produced. 6 Thermocouples are very precise in measuring temperatures is the reference junction temperature does not change of the time period of the measurements.
The voltage signal produced by the thermocouple can be converted to electrical signal in many ways. One way to do this is by using a power serials polynomial. The coefficients in the power series are known for each thermocouple type and using the thermocouple output voltage, temperature can be calculated. 6
E = A0 + A1T +A2T2 +A3T3 +…. + AnTn Equation (4)
E is the thermoelectric voltage in micro volts and T is temperature at the measurement junction. The coefficients are constants and are different for different thermocouples.
Thermodynamics is essentially how heat energy transfers from one substance to another. In “Joe Science vs. the Water Heater,” the temperature of water in a water heater must be found without measuring the water directly from the water heater. This problem was translated to the lab by providing heated water, fish bowl thermometers, styrofoam cups, and all other instruments found in the lab. The thermometer only reaches 45 degrees celsius; therefore, thermodynamic equations need to be applied in order to find the original temperature of the hot water. We also had access to deionized water that was approximately room temperature.
The respirometer uses the principle of water displacement. As the amount of gas in the respirometer changes, this will be reflected by an equivalent displacement of water in the pipette. Remember that at the same temperature and pressure,...
The purpose of this lab was to calculate the specific heat of a metal cylinder
The purpose of the lab is to understand how to calculate the calorimeter constant by using a calorimeter. This allows us to analyze the heat reaction of different substances. Calorimetry is a word that comes from both Latin and Greek. The prefix “Calor” in Latin signifies heat and the suffix “metry” in Greek means measuring. Therefore the word itself translates to measuring heat. Joseph Black, was the first scientist to recognize the difference between heat and temperature. Energy is always present in chemical and physical changes. The change of energy that occurs when there is a chemical change at constant pressure is called enthalpy. Enthalpy changes , as well as physical and chemical changes, can be measured by a calorimeter. The energy that is released or absorbed by the reaction can be either absorbed or released by the insulating walls of the instrument.
We must first begin the today’s lab by connecting the thermometer that digitally detects surrounding temperature to the Lab Pro Interface located on the computer via...
I found that my thermometer was slightly inaccurate, due to my measurements. Nothing is exact or perfect, but the thermometer is very close to accurate, being off in between 0.1-1°. This taught me that you cannot always trust a thermometer. The work has to be done by you individually to know what is really going
A thermometer * A clamp * A Bunsen burner * A stop clock Method = =
A hot plate is acquired and plugged in and if left to warm up. Fill two beakers with 0.075kg of water and record the temperature using a thermometer and record it. Place one of the beakers onto the hot plate and drop one of the metal objects in. Wait for the water to boil and wait two minutes. Take the object out of the water and drop it into the other beaker. Take the temperature of the beaker and record the rise in temperature.
Background Knowledge -------------------- Pressure The three scientists Boyle, Amontons and Charles investigated the relationship between gas, volume and temperature. Boyle discovered that for a fixed mass of gas at constant temperature, the pressure is inversely proportional to its volume.
Measure and record the temperature of the water in the Styrofoam cup. Leave cardboard cover on until the heated metal is ready to be transferred into the calorimeter.
- Temperature was measured after and exact time i.e. 1 minute, 2 minutes, 3 minutes.
Quantitative measurements on gases were first made in a rational manner by the English chemist Robert Boyle (1627 - 1691). The instruments used by Boyle to measure pressure were two: the manometer, which measures differences in pressure, and the barometer, which measures the total pressure of the atmosphere.
in chemical operations, minimization of building heat losses using improved insulation techniques, thermal control of space vehicles, heat treatment of metals, dispersion of atmospheric pollutants. A thermal system contains matter or substance and this substance may change by transformation or by exchange of mass with the surroundings. To perform a thermal analysis of a system, we need to use thermodynamics, which allows for quantitative description of the substance. This is done by defining the boundaries of the system, applying the conservation principles, and examining how the system participates in thermal energy exchange and
The thermoelectric effect refers to phenomena by which either a temperature difference creates an electric potential or an electric potential creates a temperature difference. Conversion between electrical and thermal energy is possible because of two important thermoelectric effects: Seebeck effect (converting temperature to current) and Peltier effect (converting current to temperature). Direct conversion of thermal and electric energy means that the thermoelectric devices are often more reliable than traditional mechanic devices and suffer less wear. Thermoelectric devices have a much lower efficiency than traditions devices. While all materials have a nonzero thermoelectric effect, in most materials it is too small to be useful. However, low-cost materials that have a sufficiently strong thermoelectric effect (other required properties) could be used in application including power generation and
My aim is to see the effects of a change in temperature on the rate of