Dumpster Galileo Thermometer
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- Опубліковано 28 лис 2023
- I found this Galileo Thermometer in the dumpster!
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Got one of those. Hottest is over 30C, lowest I think 16C, something like that. I like it, never had to change the batteries or update the cloud subscription. Works a treat.
As a child I saw these in shops and thought they were for wizards.
For me, the most peculiar thing is not the workings of the thermometer, but why people throw things like this away...😮
People throw gold, diamonds and money away.
Maybe in the office controlled climate, the thermometer never actually changed ... leaving it a bit static. Much better to have it at home where the temperature can vary quite a bit (at least in my home it does).
It costs like 30 bucks.
@@user93237 The small ones do. The bigger ones like this are about $100.
Honestly, hey're very common and cost like $10. I have two in my house somewhere that I haven't looked at in 20 years.
I'm amazed this wasn't smashed to pieces in the dumpster. Great find and a lovely scientific ornament.
The actual temperature is read from the lowest floating vial. Curiously, mine is spot on with a type K thermocouple. And 24C in the lab as perfect for labbing. Good on ya Dave!
No, the current temperature will be indicated by the bulb that is right in the middle. If 22C is at the bottom then the temp is above 22C. In this case there is no bulb in the middle, so it's somewhere between 22C and 24C, but it's definitely not 22C (assuming absolute accuracy)
27 °C would be better as it's the default SPICE temperature (300K) 😁
these are awesome, My late mother had one and never saw them move but did see them different
and you should totally put it in the background for videos so we know how hot your content is :-P
I had one of these when I was younger. My mom thought it was some sort of fancy glass pleasuring device and I had to tell her what it was. So weird.
Wow Dave, this is cool, never heard about these
Dave, maybe you can show us this in action by heating it
You can do that just by putting your hands on it.
If that is a thermometer, I sure hope it is not the rectal type.
...well, I'm sure someone somewhere on this earth must have taken this challenge upon themselves. Hopefully they succeeded.😂
it can be used for that too if you are brave enough
These were in all the trendy gift shops about 10 years ago. I used to have one, I think an ex-girlfriend nicked it ☺
I have a smaller version of that in F instead of C. pretty neat, would love to get one with 1* resolution.
We need Timelapse, of course not in your lab where the temperature is steady.
I love this type of thermometer. Still have one but haven't seen it in years. Im getting tired of everything being digital and caught out because the damn digital garbage is broken with no backup.
nice ornament
Could you do a time-lapse of this thing heating up or cooling down?
Vertical video, ugh.
I'm surprised you have two degree increments on this. The one I have at home increments by two Freedom units which is about 1.1 science units.
I am your density...
wait your not going to heat it up and cool it off so we can see it do its thing ?
I’ve got one of those, cost me £200 about 30 years ago
The incredible handshake of science:
Density: ρ = m/V, where p is the density, m is the mass and V is the volume.
...............................................................................
Pressure: p= F/A, where: p is the pressure, F is the magnitude of the normal force, A is the area of the surface on contact.
.......................................................................................................
Temperature: the degree or intensity of heat present in a substance or object
................................................................................................................
The Combined Gas Law shows that the pressure of a gas is inversely proportional to volume and directly proportional to temperature. Avogadro's Law shows that volume or pressure is directly proportional to the number of moles of gas. Putting these together leaves us with the following equation:
P1×V1T1×n1=P2×V2T2×n2
As with the other gas laws, we can also say that (P×V)(T×n)
is equal to a constant. The constant can be evaluated provided that the gas being described is considered to be ideal.
The Ideal Gas Law is a single equation which relates the pressure, volume, temperature, and number of moles of an ideal gas. If we substitute in the variable R
for the constant, the equation becomes:
P×VT×n=R
The Ideal Gas Law is conveniently rearranged to look this way, with the multiplication signs omitted:
PV=nRT
...............................................................................................................................
p= ρgh, where:
p is liquid pressure,
g is gravity at the surface of overlaying material,
ρ is density of liquid,
h is height of liquid column or depth within a substance.
Another way of saying the same formula is the following:
p= weight density x depth
..............................................................................................
We can calculate the heat released or absorbed using the specific heat capacity
\[\text C\], the mass of the substance
\[\text m\], and the change in temperature
\[\Delta \text T\] in the following equation:
\[\text q = \text{m} \times \text C \times \Delta \text T\]
...................................................
0th Law of Thermodynamics
The Zeroth Law of Thermodynamics states that if two systems are in thermodynamic equilibrium with a third system, the two original systems are in thermal equilibrium with each other. Basically, if system A is in thermal equilibrium with system C and system B is also in thermal equilibrium with system C, system A and system B are in thermal equilibrium with each other.
1st Law of Thermodynamics
The First Law of Thermodynamics states that energy can be converted from one form to another with the interaction of heat, work and internal energy, but it cannot be created nor destroyed, under any circumstances.
2nd Law of Thermodynamics
The Second Law of Thermodynamics states that the state of entropy of the entire universe, as an isolated system, will always increase over time. The second law also states that the changes in the entropy in the universe can never be negative.
3rd Law of Thermodynamics
The 3rd law of thermodynamics will essentially allow us to quantify the absolute amplitude of entropies. It says that when we are considering a totally perfect (100% pure) crystalline structure, at absolute zero (0 Kelvin), it will have no entropy (S). Note that if the structure in question were not totally crystalline, then although it would only have an extremely small disorder (entropy) in space, we could not precisely say it had no entropy.
.....................................................................................................
Density
The density of a liquid can be expressed as
ρ = m / V (1)
where
ρ = density of liquid (kg/m 3 )
m = mass of the liquid (kg)
V = volume of the liquid (m 3 )
The inverse of density is specific volume:
v = 1 / ρ
= V / m (2)
where
v = specific volume (m 3 /kg)
Volume and change in Temperature
When temperature increases - most liquids expands:
dV = V 1 - V 0
= V 0 β dt
= V 0 β (t 1 - t 0 ) (3)
where
dV = V 1 - V 0 = change in volume - difference between final and initial volume (m 3 )
β = volumetric temperature expansion coefficient (m 3 /m 3 o C)
dt = t 1 - t 0 = change in temperature - difference between final and initial temperature ( o C)
(3) can be modified to
V 1 = V 0 (1 + β (t 1 - t 0 )) (3b)
Density and change in Temperature
With (1) and (3b) the final density after a temperature change can be expressed as
ρ 1 = m / ( V 0 (1 + β (t 1 - t 0 ))) (4)
where
ρ 1 = final density (kg/m 3 )
- or combined with (2)
ρ 1 = ρ 0 / (1 + β (t 1 - t 0 )) (4b)
where
ρ 0 = initial density (kg/m 3 )
Volumetric Temperature Coefficients - β
water : 0.0002 (m 3 /m 3 o C) at 20 o C
ethyl alcohol : 0.0011 (m 3 /m 3 o C)
volumetric expansion coefficient for some commonly used materials
Note! - volumetric temperature coefficients may vary strongly with temperature.
Density and change in Pressure
The influence of pressure on the volume of a liquid can be expressed with the three dimensional Hooke's law
E = - dp / (dV / V 0 )
= - (p 1 - p 0 ) / ((V 1 - V 0 ) / V 0 ) (5)
where
E = bulk modulus - liquid elasticity (N/m 2 )
The minus sign corresponds to the fact that an increase in the pressure leads to a decrease in volume.
With (5) - the final volume after pressure change can be expressed as
V 1 = V 0 (1 - (p 1 - p 0 ) / E) (5b)
Combining (5b) with (1) - the final density can be expressed as:
ρ 1 = m / ( V 0 (1 - (p 1 - p 0 ) / E)) (6)
- or combined with (2) - the final density can be expressed as
ρ 1 = ρ 0 / (1 - (p 1 - p 0 ) / E) (6b)
Shameful what people discard, when they could just gift these things to people or donate them.