How Much Will Mercury Rise in a Thermometer Due to Thermal Expansion?

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1. A mercury thermometer has a bulb of volume .100 cm^3 at 10degreesC. The capillary tube (initially empty) above the bulb has a cross-sectional area of .00012 cm^2. How much will the mercury rise when the temperature rises by 30degreesC? Ignore the thermal expansion of the glass bulb and tube. (beta of mercury = 1.8 x 10^-4 degreeC^-1)


Homework Equations


Q = mcdT
H = kAdT/L


The Attempt at a Solution


I tried plugging in numbers for H = kAdT/L and I'm not sure what the "beta of mercury" is. I'm pretty bad at thermo.
 
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The "beta of mercury" is the thermal expansion coefficient of mercury, which describes how much the liquid's volume changes with temperature.

Remember: If you are stuck trying to figure out what a given coefficient/constant is for, have a look at the units, here you have units of inverse temperature, so this coefficient MUST describe how something changes with respect to temperature.

Helpful... or do you need more guidance?
 
npupp said:
The "beta of mercury" is the thermal expansion coefficient of mercury, which describes how much the liquid's volume changes with temperature.

Remember: If you are stuck trying to figure out what a given coefficient/constant is for, have a look at the units, here you have units of inverse temperature, so this coefficient MUST describe how something changes with respect to temperature.

Helpful... or do you need more guidance?

Thank you so much
 
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The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?
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