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To save materials and thus costs of production Umm yeah you are 100% wrong. They are so narrow so that the liquid doesn't slide up and down the thermometer when u take it out of your mouth and try to read it. Adhesion allows the liquid to cling onto the tube which keeps the liquid stationary.
Actually, you're both...mostly wrong. The alcohol/Mercury expands when heated. For this reason, the thin tube allows for one to see the change in temperature, whereas a wider tube would result in more subtle and difficult to read changes.
What else can I help you with?
What is the use of fuse in fluorescent tube?
Fuse is used to restrict the flow of current to the tube when it is supplied with very high voltage. Due to high voltage the tube may burst and even the electrical apparatus goes malfunctioning. Hence a resistor is used in the name of FUSE in the fluorescent lamp to prevent this sudden loss of the apparatus.
What is the difference between vacuum tubes and transistors?
A vacuum tube is a current amplifier where the transistor amplifies voltageA tube is a voltage amplifier. A transistor is a current amplifier. A tube is an older design that requires substantial voltage to operate correctly. A transistor is a semiconductor device that operates on relatively low voltage.
Whtat is the invention that made possible a revolution in electronics?
The really radical change in electronics was the invention of the transistor. It was not very pretty, it was not very big, but the world was made a far better place because of it
Why is the base of transistor made very thin?
Base of transistor is made thin just to get Collector current equal to Emitter current.
Swamping resistor is made up of?
Swamping resistor is mostly made of manganin or constantan because these materials have temperature coefficients very close to zero thus there is a very less change in the resistance of these materials with change in temperature.
Describe the structure of a thermometer?
The thermometer consists of a very fine glass tube having a very small bore and is called capillary tube. At one end of capillary tube a very thin glass bulb is provided. The bulb is filled with mercury( most of the times) or alcohol The other end of capillary tube is sealed. The capillary tube is protected by a thick glass tube called stem. On the stem are made markings. These markings are called graduations or degrees.
What is thermometer made up of?
In this answer I m referring to the normal thermometers. Not the electronic thermometers. There is a very very thin capillary tube incide the thermometer which is filled with mercury and it has a bulb aT one end. When it touches a surface, the mercury expands, rises in the capillary and the temperature is shown.
How does a thermomerator measure temperature?
that depends on what type of thermometer. The tube thermometer, the kind with a glass tube with a red liquid in it, uses a small amount of mercury in a very small tube. When the mercury is heated, it expands, pushing further up the tube, as it cools it contracts, going down the tube. A dial thermometer also works on expansion and contraction, but with a coil instead of mercury.
Why do you rotate the stem of the clinical thermometer when you read the thermometer?
If it is an analog thermometer, the face of the thermometer is shaped in a way that magnifies the readout, but it has a very narrow angle of visibility. Once rotated to the proper angle, the once thin line becomes a thick, easy to read line.
Describe what a blood capillary look likes?
A very narrow organic flexible tube
What is a scientific term for the ability of water molecules to rise up a very narrow tube?
That's called - 'capillary action'.
Function of cork borer?
Very simple answer: to make a hole in a cork or plastic stopper; the scope is to insert a tube, thermocouple, thermometer, etc.
What are the London streets like?
Very narrow and usually made of brick.
What is a loop reactor?
A bulk (slurry) polymerisation reactor which is made of a closed long tube through which the slurry is circulated. Loop reactors are characterised by a very narrow residence time distribution, leading to uniform product characteristics.
Why is the bore of the capillary tube of a mercury thermometer made narrow?
Answer Vapour Pressure and Precisiondh25sThe vapour pressure of mercury (Hg) is low (0.0017 torr at 25 oC). The vapour pressure is dependent on temperature, thus what you want to measure. As the temperature increases, the vapour pressure increases and the mercury imbibes further up the capillary. If the capiallry radius were larger, the readings would be more difficult to see, i.e. the precision would decrease. Vapor pressure has nothing to do with how a Mercury thermometer works. As the temperature rises, the mercury expands into a narrow bore, because the volume of the mercury increases. If the bore is very narrow then the extra volume has to go a longer way up the bore to accomodate that volume, so it is more sensitive to small changes of temperature.
How do you fix a thermometer where the mercury is separated in the tube?
You can't and shouldn't repair this. Mercury being poisonous, it is best recommended to discard the whole thermometer, without letting the mercury escape, very carefully. Maybe where you live they have a special place where such objects are destroyed safely.
Why is the bulb in a thermoniter important?
The bulb in a thermometer increases the sensitivity.When the temperature changes in the bulb, the mercury or other fluid will go up or down the narrow tube. The reason for this is due to change in the volume caused by expansion of the mercury or fluid; as the temperature increases, the volume increases.However, the change in volume may be very small, so by having a narrow tube, any movement caused by expansion will be more visually noticeable.To illustrate this, imagine two tubes containing 10ml of fluid each at 20oC. One tube is 1cm in diameter, the other 0.1cm. By using the equation for the volume of a cylinder we can calculate the height of the fluid in the tubes, (remember that 1ml = 1cm3)In 1cm diameter tube:Volume of fluid = pi x radius2 x height of fluid in tube10cm3 = pi x (0.5cm)2 x height of fluid in tubeHeight of fluid in tube = 10 / ( pi x 0.52 ) = 12.73cmIn 0.1cm diameter tube:Volume of fluid = pi x radius2 x height of fluid in tube10cm3 = pi x (0.05cm)2 x height of fluid in tubeHeight of fluid in tube = 10 / ( pi x 0.052 ) = 1273cmAs can be seen, the height of fluid in the smaller tube is much greater as the same amount of fluid has to fit into a smaller space. Now imagine that for a 1oC change in temperature the fluid expands 1% in volume. So at 21oC the 10ml of fluid expands 1% to 10.1ml (10ml x 1.01 (1%) = 10.1ml). Now we can calculate how much movement this would create in the tubesIn the 1cm diameter tube:Volume of fluid at 21oC = pi x radius2 x height of fluid in tube at 21oC10.1cm3 = pi x (0.5cm)2 x height of fluid in tube at 21oCHeight of fluid in tube at 21oC = 10.1 / ( pi x 0.52 ) = 12.86cmSo the fluid in the 1cm diameter tube has moved:Height at 20oC - Height at 21oC = Movement of fluid12.86cm - 12.73cm = 0.13cmWhilst in the 0.1cm diameter tube the fluid has moved:Height at 20oC - Height at 21oC (calculation not shown) = Movement of fluid1286cm - 1273cm = 13cmAs you can see, the movement in the smaller tube would be much more noticeable than in the larger tube and this would mean that even very small temperature changes could be visualised as the fluid moves a lot further. So that is why the central tube is so small, but why the bulb?In the example just shown both tubes had the same volume of starting fluid, 10ml. But, as you saw, 10ml in a 0.1cm diameter tube requires a tube of over 12 metres, a very impractical size for a thermometer! One way to solve this is to reduce the amount of starting fluid to 0.1ml.In the 0.1cm tube:Volume of fluid = pi x radius2 x height of fluid in tube0.1cm3 = pi x (0.05cm)2 x height of fluid in tubeHeight of fluid in tube = 0.1 / ( pi x 0.052 ) = 12.73cmNow we have a thermometer, which although large, could be used. But, look what happens when we increase the temperature to 21oC. The fluid expands to 0.101ml (=0.1ml + 1%) and the new height of fluid in the 0.1cm diameter tube is:Volume of fluid at 21oC = pi x radius2 x height of fluid in tube at 21oC0.101 cm3 = pi x (0.05cm)2 x height of fluid in tube at 21oCHeight of fluid in tube at 21oC = 0.101 / ( pi x 0.052 ) = 12.86cmThis gives a change in height from 20oC to 21oC of only 0.13cm. We have lost the sensitivity given by the smaller tube.Therefore, to make a sensitive thermometer we need a large volume and a narrow tube. So how do we do this without making a thermometer too big to use? By adding the bulb. The bulb is a lot wider than the narrow tube of the thermometer and is therefore able to hold a larger amount of mercury or fluid. But if the entire tube was the same width as the bulb, any expansion would be difficult to see. So by combining the bulb, with its ability to hold a large volume of mercury or fluid, with the narrow tube, with its ability to cause large movement of fluid for a small amount of expansion, we create a sensitive thermometer.So to give a short answer, the bulb increases sensitivity by increasing the volume of mercury or fluid inside the thermometer causing greater amplification of expansion, or movement, up the narrow tube. So more volume = greater movement = greater sensitivity.The bulb in a thermometer increases sensitivity. It helps determine whether the fluid will go up or down. The bulb helps make a sensitive thermometer and it helps in holding a larger amount of mercury or fluids than the narrow tube.
