what is a thermistor?
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thermistor is a type of resistor used to measure temperature changes, relying on the change in its resistance with changing temperature. Thermistor is a portmanteau of the words thermal and resistor.\n\nIf we assume that the relationship between resistance and temperature is linear (i.e. we make a first-order approximation), then we can say that:\n\nΔR = kΔT \nwhere\n\nΔR = change in resistance \nΔT = change in temperature \nk = first-order temperature coefficient of resistance \nThermistors can be classified into two types depending on the sign of k. If k is positive, the resistance increases with increasing temperature, and the device is called a positive temperature coefficient (PTC) thermistor, posistor or sensistor. If k is negative, the resistance decreases with increasing temperature, and the device is called a negative temperature coefficient (NTC) thermistor. Resistors that are not thermistors are designed to have the smallest possible k, so that their resistance remains almost constant over a wide temperature range.
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thermocouples are used to measure high temperatures.  click on the link for an explanation on how a thermocouple works.
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Galvanometer;An Instrument used to Detect or Measure small electric currents by means of mechanical effects produced by an Induction Coil. Ammeter; An Instrument that measures Electric Current by being actively connected to an Electrical Circuit.
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A tuning Fork...Is something that vibrates when you hit it.It's used to analyze sound frequencies and variations.\nA Spectrometer...Is used to analyze light under different angles\nA Potentiometer...Is a piece of equipment that would allow you to calculate the potential of a battery connected to it...\nA magnetometer....Is an instrument used to measure the strength and/or direction of the magnetic field in the vicinity of the instrument....\nA lens...is a device that causes light to either converge and concentrate or to diverge...\nA thermometer is an instrument used to measure temperature or temperature gradient...
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All the thermos does is prevent (or slow down) the transfer is heat energy.\n\nHeat always flows from hot to cold.  If you put a hot liquid into the thermos, then the outside air is cooler than the inside, so natually, heat tends to flow out of the thermos.  If you put a cold liquid into the thermos, heat tends to flow into the thermos from the relaitvely warmed air outside.  What the thermos does is try to prevent this transfer of heat so your hot liquids stay hot and your cold liquids stay cold longer.
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A leader takes charge and a manager just has a position and watches others take charge.  A manager just watches what happens and guides. A leader sets what is going to happen.  Someone leading a leadership workshop once asked me am I a themometer or a thermostat?  I wasn't sure.  It was explained to me that a themometer(manager) mesures the temperature, a thermomstat sets the temperature.  so be the thermostat that sets the standard.
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Infra red thermometer
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transducer is a general term for a sensor that changes an physical reading (maybe temperature, position, humidity) to an electrical signal (0 to 5 volts for example).MIKE
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Oxygen Sensor - an electronic device that measures the proportion of oxygen in the gas.
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flask - container for substances\nweight -  to measure weight\nspatula - kind of spoon\nbunsen burner - used for heating and boiling\nasbestos - used to protect something from burning
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Any temperature-sensing device whose resistance is a function of temperature is inherently nonohmic; i.e., does not display a constant resistance with varied current flow or varied applied voltage. This is due to the fact that current flow will cause the device to heat and do its job which is to change resistance. An NTC device could conceivably "run away" with a constant applied voltage; as current increases it heats up and its resistance goes down resulting in further current increase. Conversely, a PTC device could conceivably run away with a constant applied current; as it heats up its resistance increases resulting in a higher voltage drop across it, which produces more heating, etc. For this reason, when using a thermistor it is a good idea to measure its resistance with a very sensitive (low sensing voltage and current) ohmmeter to minimize spurious heat input.
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The most commonly utilized sensor for measuring temperature are still the mercury thermometers. Maximum and minimum thermometers use mercury and alcohol. Bimetallic thermographs are the most common mechanical temperature recorders. They are easy to read and maintain. However, mechanical thermographs do require verification and adjustment of the position of the pen recorder. These instruments are installed in shelters that are naturally ventilated.
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My colleague above defined a heat exchanger.\n\nA regenerator in thermodynamics is a heat exchanger tha uses the remaining heat of waste fumes to preheat the cold air entering combustion, for example.\n\nUsing define in Google:\n\nSame as recuperator except the gaseous products of combustion heat brick checkerwork in a chamber connected to the exhaust side of the furnace while the incoming air and fuel are being heated by the brick checkerwork in a second chamber, connected to the entrance side. At intervals, the gas flow is reversed so that incoming air and fuel contact hot checkerwork while that in the second chamber is being reheated by exhaust gases.\nwww.tdcoating.com/td_glossary_terms7.htm\n\nYou should also check www.globalspec.com and get some brochures in the sites listed. \n\nIf you are hesitating in this perhaps you should go back to college :>
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"Temperature" is the measure of the average kinetic energy of the particles of a substance.\nIn the case of using a thermometer to measure temperature, the temperature of the thermometer is what is actually being seen in the measurement, we just assume that it has come to thermal equailibrium (no net flow of heat energy) with the surroundings.\n\nSince a vacuum is totally empty (i.e. no particles), a vacuum does not have a temperature by definition.\n\nIf we also assume this vacuum system is isolated from the rest of the universe and that the walls are perfect reflectors, then the temperature reading on the thermometer will not change when placed into a vacuum....but remember the conditions which we just had to apply.\nThere are 3 methods in which heat [energy] is transfered, through conduction, convection, and radiation.  In a vacuum, conduction and convection are inappliacble in terms of carrying heat away from the thermometer (or to the thermometer).  However, radiation is still quite possible, and likely.  The thermometer will emmit Infra red radiation in the form of photons of light which will carry away heat energy from the thermometer (lowering its temperature).  Likewise, if we allow any other EM radiation to some into the box, it may increase the heat energy of the thermometer (and raise its temperature).  If we assume the box is isolated and its walls are perfect reflectors (which will refrlect 100% of any EM radiation the thermometer emmits back), then the thermometer's heat energy should remain constant as will its temperature.
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a thermostat measures the amount of thermal energy present.  one common type of thermostat uses two strips of metal with different coefficients of thermal expansion glued together.  That way as the temperature changes one strip changes length more then the other and they curl.
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an anameter  -it is used fr measuring current passing through the circuit.\n\n conical flask -its flat bottemed used to hold liquids in reactions where heating is not required.\n\nburette -used to add one solution to another and also acurately measures the amount of liquid used.\n\ndropper pipette -used to add small but accurate amount of liquid to another.\n\nfunnel - used to carry out filtration.\nboiling tube-made of thick resistant glass used fr strong heating.\n\nround bottemed flask-used to hold liquids in reations where heating is required.\n\nwatch glass-holds solids\n\nevaporating dish-it can be gentely heated\n\nmortar and pestle-fr grinding and mixing solids\n\ngud luck!hope it helps
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Impedance is related to alternating current Circuits.\nResistance is related to direct curent circuits. It has the Unit of inverse velocity. hence resists the motion of electrons in a conductor and as a result dissipates heat energy.Hence it is considered as a heat dissipating device..\n\nReactance is an energy storing device and is associated with coils which are magnetic energy producing device.\n\nHence a reactance stores energy and then gives it back .\n\nImpedeance is the sum of resistance  plus reactance but reactance is 90 degrees out of phase. Hence reactance is \ndescribed as imaginary quantity where resistance is real quantity.\nResistance is real because it dissipates energy and reactance is imaginary be cause it stores energy as magnetic and does not dissipate as heat energy.\nImpedeance in a circuit folows the same circuit rules as resistance.