Ambrose Swasey
  • Member for 7 years, 5 months
  • Last seen more than a week ago
How does a river freeze when the water keeps moving?
26 votes

The river does not freeze in its moving parts. It begins to freeze from the banks in places where the water is motionless or nearly so. Then the frozen area gradually grows towards the center of the ...

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Why don't miners get boiled to death at $4$ km deep?
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8 votes

After doing some more research on this question I have determined, like the other answers, the reason that the miners do not boil to death is that they cool the mine actively. Originally this was done ...

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Fired a bullet upwards, can it fall down and kill me?
4 votes

There is always air resistance, unless you are in space. If there was no air resistance, a bullet would land at the same speed it was shot at. On Earth, a spent bullet is rarely lethal. In big wars (...

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What is the technology that uses a rectangular mask to do high focus imaging?
2 votes

It is generally just called "lenseless imaging" and was first used to in x-ray crystallography. The mask is referred to as a coded aperture or phase imaging.

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The thickness of a puddled sheet of water
2 votes

Based on the page linked in the comments, the answer seems to be the following: (1) The height of the puddle does not depend on the material of the surface so long as the surface is nonwetting. (2) ...

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How can I measure a length of over 4 feet to an accuracy of 1/100th of an inch?
2 votes

After some significant research, I have figured out how to do this. You make a linear measurement array using precision 1.0000" balls in right angle v-groove with a base plate, and then a matching ...

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Why does the sun appear yellow?
1 votes

Using some of the links in the comments and other research I have figured out the answer to the question. The answer is that the apparent color for any source of light is due to the addition of the ...

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Why is the colour of sunlight yellow?
1 votes

The reason why the sun is yellow is because the color is determined by additive combination of its component spectrum. In other words, the sun emits a range of light that we can see, from violet to ...

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Why doesn't NASA use RAMJET rockets to get into space?
1 votes

There has been ongoing interest in air-augmented rockets which use ramjet technology. The main technical problems are that: (1) They are significantly heavier than regular rockets. (2) The need for ...

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Measuring precise distances over a table top range
1 votes

I did further research on this problem and discovered that the relevant technology is called displacement measurement interferometry or DMI. There are two basic types of instruments: a homodyne and ...

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Use of tungsten as an insulator in an induction heater
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1 votes

After doing more research I found the following table on IR reflectivity: From this it appears silver is by far the best reflector, rhodium is #2 and platinum is number 3. Silver melts at forging ...

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How can the rate of convection up a chimney be computed?
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0 votes

Based on one of the comments, I found that there is a draft flow rate equation as follows: where: Q = stack effect draft flow rate, ft3/s A = area, ft2 C = discharge coefficient (usually from ...

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Good way to compute the force of a hammer blow?
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0 votes

I did some more research on this question and read some old books on the subject written back in the days when America still had blacksmiths. What I found out is that there are two basic stages in ...

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Does car tire pressure change with weight of car load?
0 votes

Obviously the pressure increases with load. If it didn't then you could have an infinite load! If the load is increased, eventually the pressure will increase to the point where the tire bursts (or ...

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Rayleigh-Jeans Law difference between the frequency and wavelength forms
0 votes

As ACuriousMind notes, the answer is indeed in the same Wikipedia article I link. The wavelength-based radiance is given in units of energy emitted per unit time per unit area of emitting surface, per ...

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Calculate heat transfer out of a basement
0 votes

After studying this problem, I have found a method of solving it. First of all, since the ceiling is the heat source, we don't know what it needs to be to keep the room at 10 degrees C. Obviously it ...

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What causes atoms to have their specific colors?
-1 votes

First of all, color is not reflected. When light is reflected it creates glare which is an image of the light source itself. Color is created either when (1) light of a particular wavelength is ...

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Why can we only "see" reflected light?
-2 votes

I think you have a fundamental misapprehension of the way light interacts with an object. Most objects do not reflect light. They absorb light and re-emit it. When you see regular objects like a house ...

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Conversion of angular momentum to linear momentum in free space
-4 votes

Yes, I just did a thought experiment that shows that indeed angular momentum will be converted to linear momentum. Imagine we have two gyroscopes or tops spinning on a table. The tops each spin ...

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