The volume tag has no wiki summary.
2
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2answers
70 views
Why is it faster (as in proportion to volume) to boil 4 cups of water than to boil 2 cups?
I did an experiment where I boiled two cups (500ml) of water in a kettle, and it took 1:30 minutes to reach around 98 C, average. However, when I boiled 4 cups of water, (1L) it only took me 2:30 ...
0
votes
0answers
21 views
Over-inflating weather balloons
Would it be safe to over-inflate a weather balloon if it isn't going to be used at high altitudes? I've been looking at several different balloons, but they are all measured by their burst diameter ...
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0answers
26 views
What is the ration of volume to lift helium? [closed]
I've been searching for a usable direct conversion, but most of what I've found used a lot of rounding. What is the exact formula?
4
votes
2answers
72 views
What is the entropy of a system when its volume tends to zero?
Say that a closed system has $n$ dimensions and is in the shape of a $n$-ball with a radius of 1, it's volume will be
$$\frac{\pi^\frac{n}{2}}{\Gamma(\frac{n}{2}+1)}$$
which tends to 0 yet is not ...
1
vote
2answers
46 views
How is it possible to equate the internal energy at constant volume with the internal energy of an adiabatic process?
I hope my question makes sense. My problem is that, I have read through numerous textbooks that nC(cons. volume)dT = -PdV when deriving the relationship between T and V for an adiabatic process, ...
5
votes
2answers
216 views
Do black holes have infinite areas and volumes?
How to calculate the area / volume of a black hole?
Is there a corresponding mathmetical function such as rotating 1/x around the x-axis or likewise to find the volume?
11
votes
1answer
331 views
Why does my natural whistle have a maximum volume
When I whistle, I find that I can vary the volume by pushing more or less air through my mouth at once. However, when I increase volume past a point, I start to hear a blend of rushing air and a ...
2
votes
1answer
190 views
Thermal expansion of Sphere
How would one go about writing an expression of the expansion of the volume of a sphere of a given material? I noticed a few sources give it as
$\Delta V= 3\gamma V\Delta T $
where V is the initial ...
1
vote
3answers
119 views
Does the volume of a thermodynamic system always have to change for it to do work?
Does the volume of a thermodynamic system always have to change for it to do work?
If yes,could you explain why?
And if no, could you provide the example of a system, where it is not neccesary.
1
vote
2answers
874 views
Thermodynamics - Sign convention
I use the sign convention:
Heat absorbed by the system = $q+$ (positive)
Heat evolved by the system = $q-$ (negative)
Work done on the system = $w +$ (positive)
Work done by the system = $w -$ ...
1
vote
2answers
131 views
The physics behind The Great Flood [closed]
The book of Genesis floats (pardon the pun) some interesting numbers when discussing the Great Flood. For example, it rained for 40 days and 40 nights, and at the end of that time, the entire planet ...
0
votes
1answer
134 views
What is the particle residence time for given flow rates of gas mixture components?
For two different chemical substances there are two open valves with flow rates $$Q_1=a\frac{m^3}{h}\ \text{ and }\ \ Q_2=b\frac{m^3}{h},$$ leading into seperate cables.
Next, the cables join, the ...
2
votes
2answers
79 views
The appearance of volume $V$ in the Fourier series representation of a periodic cubic system
In the textbook Understanding Molecular Simulation by Frenkel and Smit (Second Edition), the authors represent a function $f(\textbf{r})$ (which depends on the coordinates of a periodic system) as a ...
1
vote
1answer
621 views
Calculate mass of air in a tyre from pressure
How can one calculate the mass of air inside a tyre, given a particular tyre size; a pressure, in $kPa = \frac{1000kg}{m\cdot s^2}$; and assuming room temperature, and normal air composition? I can't ...
2
votes
1answer
312 views
Gas Cylinder Life
Say I have a gas cylinder filled with nitrogen to some volume at some pressure. On that cylinder I have a regulator so that I get a steady pressure out. I wish to discharge the cylinder. How many ...
7
votes
2answers
205 views
Do you pay more for gas when the day is warmer?
Found this at the gas station yesteday - got me thinking...
2
votes
4answers
1k views
What kinds of materials contract the most in cold temperatures?
I know that water expands in the freezer, but I'm curious about which materials contract in response to cold temperatures --- and most importantly, which ones undergo the most drastic changes?
2
votes
4answers
6k views
Why are volume and pressure inversely proportional to each other?
It makes sense, that if you have a balloon and press it down with your hands, the volume will decrease and the pressure will increase. This confirms Boyle's Law, $ pV=k=nRT $.
But what if the ...
0
votes
0answers
70 views
Vector Calculus - Mass of a block (I'm being dense) [closed]
I'm currently revising for some exams, and as part of one of my practice questions am finding the mass of a block by use of it's mass density function. It involves a triple integration as seen below. ...
1
vote
2answers
113 views
How does cooling scale with volume?
What equation would give me the answer to the question, "If i have a cup of water at a tempature of say boiling, how long would that cup of water take to cool off compared to say half that size of a ...
0
votes
3answers
134 views
What is the volume of a parcel of air of a giving weight at average sea level pressure
I know this is probably some basic math once you have the figures, but my Google-fu is failing me.
Say I have 5 pounds of air. Air meaning, the typical composition of the atmosphere of Earth. And by ...
0
votes
0answers
71 views
frequency distribution of physical body volume [closed]
I understand that physical bodies can be measured in terms of the volume that their convex hull occupies. If that volume was plotted on a histogram for all the physical bodies in the universe, that ...
5
votes
1answer
273 views
Why is the Haar measure times the volume of the eigenvalue simplex considered a good measure of Hilbert space volume?
In particular, why do we need both of these to find the volume? And should I be thinking of it as an actual volume or not?
This Hilbert space volume is talked about in this paper. It says
There ...
5
votes
4answers
1k views
Finding the volume of this irregular shape I have
I have an approximately basketball-sized non-hollow piece of aluminum sitting in my house that is of irregular shape. I need to find the volume of it for a very legitimate yet irrelevant reason.
...
