Physics help?
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anyone help .. like
THERMOMtER CHARACTERISTIC ... like Thinner bore .. thinner glass bulb .. or bigger bulb and stuff
1. Sensitivity .. wad will increase it .. or decrease it
2. Range.. wad will increase it or decrease it
3. Speed of response .. how fast can it respond .. wad will slow it or quicken it?
4. linearity .. how is it affected by the characteristic of thermometers
Thanks
Wad about characterisitc of Gd thermometer liquid
Good / Bad
like
cheap
expensive
uniform expansion and stuff
thanks ..
sorrie for lousy spelling .. damm stressed out...
hope u guys can help !
idiotboi Calls for help ! -
i assume u r talking abt thermodynamic in a clinical thermometerOriginally posted by idiotboi89:anyone help .. like
1. Sensitivity .. wad will increase it .. or decrease it
materials used
bigger bulb
2. Range.. wad will increase it or decrease it
type of luquiid used
smaller caplliary tubes
3. Speed of response .. how fast can it respond .. wad will slow it or quicken it?
bulb wall thickness
4. linearity .. how is it affected by the characteristic of thermometers
diff materials for diff range
hope i answered ur queries.. -
The substance used for thermometers affect almost all the above. Lets say you got alcohol and mercury thermometers right? How cold and hot can the mercury one go that the alcohol one cannot, and vice versa, for the range. How sensitive is a mercury thermometer compared to alcohol? Go think about the above, the rest is up to you.
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Originally posted by idiotboi89:anyone help .. like
THERMOMtER CHARACTERISTIC ... like Thinner bore .. thinner glass bulb .. or bigger bulb and stuff
1. Sensitivity .. wad will increase it .. or decrease it
depends on the range of temperture...alcohol more sensitive in cold range, Mecury in hotter range, both IDP to Bore diameter(Smaller tube more div/dTemp). Helix Bimetallic have wider temperature but less sensitive as compared to the former 2, can be compensated mechanically(gear ratio amplification, area of temperture(DP) applied to mass of bimetal(DP)). Thermocoupler can be built for sensitive in terms of 200 degreeC for specific range can be compensated electrically( amplifiers and linearlity circuits).
2. Range.. wad will increase it or decrease it
normally depends on melting and boling pt of the meterial used.
3. Speed of response .. how fast can it respond .. wad will slow it or quicken it?
thermomass and thermoconductivity.
thicker the builb slower the respond.
larger the bulb slower the respond (takes time to heat or cool some thing bigger).
surface of contact between heat source and thermometer,(larger the contact the faster it can tranfers the heat).
4. linearity .. how is it affected by the characteristic of thermometers
a little on the material of the thermometer used as they expand and contract like the other parts at different rate of the thermometer.
Physical construction
dual bulb thermometer have better linearlity then single end thermo(uses two different liquid to compensate).
normally as temp gets higher a thermo will lose its linearlity... due to increase electrical noise and resistence, reaching boiling or freezing pt etc...
Thanks
Wad about characterisitc of Gd thermometer liquid
Good / Bad
like
cheap - alcohol (common)
expensive - mercury
uniform expansion and stuff as above in pts...
gd or bad you try to see it ...
thanks ..
sorrie for lousy spelling .. damm stressed out...
hope u guys can help !
idiotboi Calls for help ! -
Wah, so advanced, secondary school physics leh.
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Just giving one rare post now that Teens Planet is being left to rot.
1. Sensitivity- A narrow bore will improve the sensitivity of the thermometer. A small change in temperature will make the expansion of the liquid more noticeable with a narrow bore.
2. Range- What is range? You mean 35 Celsius to 42 Celsius for the clinical thermometer or what?
3. Speed of response- A thin glass bulb will improve the speed of response. Heat is able to be conducted from the source to the liquid in the bulb faster with a thin glass bulb.
4. linearity- I take Combined Science, so I don't learn this.
Alcohol thermometers:
Disadvantages- Low boiling point (39 Celsius)
Colourless (must be dyed to be able to see the reading)
Advantages- Not poisonous
Low melting point (-115 Celsius)
Mercury thermometers:
Disadvantages- Poisonous
High melting point
Advantages- High boiling point
Coloured (to facilitate easier reading) -
The boiling point of alcohol is 79 degree celsius I believe not 39.Originally posted by arsenalblue:Just giving one rare post now that Teens Planet is being left to rot.
1. Sensitivity- A narrow bore will improve the sensitivity of the thermometer. A small change in temperature will make the expansion of the liquid more noticeable with a narrow bore.
2. Range- What is range? You mean 35 Celsius to 42 Celsius for the clinical thermometer or what?
3. Speed of response- A thin glass bulb will improve the speed of response. Heat is able to be conducted from the source to the liquid in the bulb faster with a thin glass bulb.
4. linearity- I take Combined Science, so I don't learn this.
Alcohol thermometers:
Disadvantages- Low boiling point (39 Celsius)
Colourless (must be dyed to be able to see the reading)
Advantages- Not poisonous
Low melting point (-115 Celsius)
Mercury thermometers:
Disadvantages- Poisonous
High melting point
Advantages- High boiling point
Coloured (to facilitate easier reading)
Disadvantage
Mecury has a high freezing point.(-39degree celcius) This means that It cannot be brought to cold places. Mercury also has low expansive properties when compared to alcohol.
Advantage
Mercury does not cling to the side of the thermometer bulb unlike alcohol.