• Does Heat Conduct Forever?

    Imagine an infinitely long metal bar. An eternal candle flame is heating the bar at one point. Presumably the heat will conduct along the bar in both directions from that point. But how far will the heat go? Will it keep spreading forever until the entire infinite bar is hot? Or does heat only conduct so far depending on the temperature of the... show more
    Imagine an infinitely long metal bar. An eternal candle flame is heating the bar at one point. Presumably the heat will conduct along the bar in both directions from that point. But how far will the heat go? Will it keep spreading forever until the entire infinite bar is hot? Or does heat only conduct so far depending on the temperature of the heating source?
    4 answers · Physics · 7 years ago
  • Faster Than Light Communication?

    I know that information can't exceed the speed of light... Therefore there's a major flaw in the following proposal. I'd be grateful to anyone who explains what the flaw is... I know that if I tried to send a message to Mars using a powerful flashlight, the light from the flashlight would take a certain amount of time to get there. But... show more
    I know that information can't exceed the speed of light... Therefore there's a major flaw in the following proposal. I'd be grateful to anyone who explains what the flaw is... I know that if I tried to send a message to Mars using a powerful flashlight, the light from the flashlight would take a certain amount of time to get there. But what if there was a solid metal bar reaching all the way to Mars with a pointer on the end that could be slid back and forth from here, so that I could spell out a message? I would pull my end of the bar and the far end would move too. Wouldn't that happen instantaneously; or at least faster than the speed of light?? Yes, I know it wouldn't really; but WHY? Is there a ripple effect in the molecules of the bar or something? What if the bar is rotated rather than slid back and forth? Looking forward to getting my mind clear on this issue!
    7 answers · Physics · 7 years ago
  • Einstein quote about eddies?

    I'm sure I read an Albert Einstein quote somewhere that mentioned about how "understanding the physics of eddies" was one of the great mysteries of nature. Maybe I'm remembering it wrongly. Or maybe it wasn't Einstein who said it... I have tried looking for the quote using Google but haven't had any success. Can anyone out... show more
    I'm sure I read an Albert Einstein quote somewhere that mentioned about how "understanding the physics of eddies" was one of the great mysteries of nature. Maybe I'm remembering it wrongly. Or maybe it wasn't Einstein who said it... I have tried looking for the quote using Google but haven't had any success. Can anyone out there help me? I'd be very grateful if you could put me right on the quote and/or the person who spoke it... Thanks!
    2 answers · Quotations · 7 years ago
  • At sunset, how many miles of Earth's atmosphere does sunlight have to pass through?

    What I mean is that at midday, the sun's rays pass through x miles of Earth's atmosphere before they reach the ground. At sunset and sunrise presumably this number x is larger. How much larger? I read somewhere that the true horizon is about 3 miles away for a 6 foot tall human. Does the sunlight at sunset only pass through 3 more miles of... show more
    What I mean is that at midday, the sun's rays pass through x miles of Earth's atmosphere before they reach the ground. At sunset and sunrise presumably this number x is larger. How much larger? I read somewhere that the true horizon is about 3 miles away for a 6 foot tall human. Does the sunlight at sunset only pass through 3 more miles of atmosphere than it does at midday? Also, how thick would the Earth's atmosphere have to be before it blocked the sunlight altogether?
    1 answer · Earth Sciences & Geology · 7 years ago
  • Photographs of Hiroshima when the bomb was dropped?

    I have read that only six photographs were taken on that day from the ground after the bomb had exploded. Yoshito Matsushige took five of them, but who took the other, and what does it show? Searching on Google has turned up nothing so far. What is the sixth photo?
    I have read that only six photographs were taken on that day from the ground after the bomb had exploded. Yoshito Matsushige took five of them, but who took the other, and what does it show? Searching on Google has turned up nothing so far. What is the sixth photo?
    2 answers · History · 7 years ago
  • In a Word document, is there a quick way of converting quotation marks?

    In a Word document, is there a quick way of converting straight 'up and down' quotation marks ["like these"] to the curved ones [“like these”] without having to go through the entire document replacing them one by one? I have a document that isn't consistent with its style of quotation mark and I want them all to be the same... show more
    In a Word document, is there a quick way of converting straight 'up and down' quotation marks ["like these"] to the curved ones [“like these”] without having to go through the entire document replacing them one by one? I have a document that isn't consistent with its style of quotation mark and I want them all to be the same kind. Thanks!
    3 answers · Other - Computers · 7 years ago
  • If we knew for sure the world was going to end soon would prices go up or down?

    I can't work out if the cost of living would be higher or lower in such a situation. Take life insurance, for instance: which way would the premiums go? Up because claims would be more likely; or down because payouts on those claims would be impossible? And what about food, books, gardening implements, booze, waistcoats, mothballs, ships?... show more
    I can't work out if the cost of living would be higher or lower in such a situation. Take life insurance, for instance: which way would the premiums go? Up because claims would be more likely; or down because payouts on those claims would be impossible? And what about food, books, gardening implements, booze, waistcoats, mothballs, ships? Cheaper or dearer?
    3 answers · Other - Society & Culture · 8 years ago
  • Can gloss varnish be applied over matt varnish?

    I varnished a painting with matt varnish and made a mess of it, all streaky lines. It occurred to me that if I re-varnish it with gloss varnish I might be able to cover the streaky matt lines and rescue the painting. But I need to know if anything weird happens when gloss varnish is applied over matt varnish. Does anyone out there know? It... show more
    I varnished a painting with matt varnish and made a mess of it, all streaky lines. It occurred to me that if I re-varnish it with gloss varnish I might be able to cover the streaky matt lines and rescue the painting. But I need to know if anything weird happens when gloss varnish is applied over matt varnish. Does anyone out there know? It doesn't leave even worse marks, does it?
    2 answers · Painting · 8 years ago
  • If a flying fish fell out of an aeroplane would it be able to glide down safely back to the sea?

    If for some reason a flying fish ended up at an altitude much higher than it is used to (e.g. 10,000 feet) would it be able to glide back down to sea level? I don't know anything about the structural integrity or aerodynamic performance of flying fish and I'm wondering if it would stall and go into an unrecoverable dive or not... A... show more
    If for some reason a flying fish ended up at an altitude much higher than it is used to (e.g. 10,000 feet) would it be able to glide back down to sea level? I don't know anything about the structural integrity or aerodynamic performance of flying fish and I'm wondering if it would stall and go into an unrecoverable dive or not... A supplementary question: would the same fish be able to perform aerobatics (loops and rolls, etc) on the way down, if it chose to?
    5 answers · Zoology · 8 years ago
  • How does one centralise a blog title?

    I have a blog on blogger.com and I want to change the font of the title and also centralise the title. I also want to put a logo in front of the title. I've messed around with the HTML on the Template but can't seem to influence the title in any way. Changing the fonts and colours for the rest of the blog is easy but the title info seems out... show more
    I have a blog on blogger.com and I want to change the font of the title and also centralise the title. I also want to put a logo in front of the title. I've messed around with the HTML on the Template but can't seem to influence the title in any way. Changing the fonts and colours for the rest of the blog is easy but the title info seems out of my reach! I must be doing something very wrong. I'd be grateful for any help on how to alter my title in this way. Thanks in advance!
    3 answers · Programming & Design · 8 years ago
  • Why doesn't the Buddha get Deep Vein Thrombosis?

    Sitting in the lotus position for eternity... Surely that can't be good for the health? This may sound like a flippant question, but in fact it's a serious one. Isn't the long inactivity associated with certain meditation postures likely to increase the chance of potentially fatal blood clots? If not, why not? (I am a Buddhist myself,... show more
    Sitting in the lotus position for eternity... Surely that can't be good for the health? This may sound like a flippant question, but in fact it's a serious one. Isn't the long inactivity associated with certain meditation postures likely to increase the chance of potentially fatal blood clots? If not, why not? (I am a Buddhist myself, but I find meditation to be almost impossibly difficult endeavour).
    7 answers · Religion & Spirituality · 8 years ago
  • Is it acceptable to sign a painting with a pen?

    Instead of signing a finished painting with a paintbrush, is it considered acceptable to sign it in ink? If so, which kind of pen would be best for this? I have a painting that I don't want to sign in paint because of its size, and a pen would be more accurate for this.
    Instead of signing a finished painting with a paintbrush, is it considered acceptable to sign it in ink? If so, which kind of pen would be best for this? I have a painting that I don't want to sign in paint because of its size, and a pen would be more accurate for this.
    5 answers · Painting · 8 years ago
  • What colour light would a black light bulb emit?

    A red bulb emits a red light; a blue bulb emits a blue light. Would a black bulb emit a black light? In other words, if a black light bulb was switched on in the daytime would it suddenly turn a bright room dark?
    A red bulb emits a red light; a blue bulb emits a blue light. Would a black bulb emit a black light? In other words, if a black light bulb was switched on in the daytime would it suddenly turn a bright room dark?
    6 answers · Physics · 8 years ago
  • How much discount should you give to friends when selling handmade crafts?

    I know someone who wants to sell their crafts and start a business but isn't sure what percentage discount is right to offer friends, family and colleagues. To give the items away fro free would scupper the business before it starts! But to charge full price seems wrong. Is there a standard percentage discount that is generally considered... show more
    I know someone who wants to sell their crafts and start a business but isn't sure what percentage discount is right to offer friends, family and colleagues. To give the items away fro free would scupper the business before it starts! But to charge full price seems wrong. Is there a standard percentage discount that is generally considered reasonable? Are the percentages for friends, family and colleagues different?
    4 answers · Other - Business & Finance · 8 years ago
  • Fujifilm Finepix A170. Any thoughts?

    Anybody care to give me their thoughts on this camera, as I'm thinking of buying one.
    Anybody care to give me their thoughts on this camera, as I'm thinking of buying one.
    1 answer · Cameras · 8 years ago
  • Do bell peppers contain a vacuum?

    Bell peppers (and chilli peppers) are hollow but they are hermetically sealed and don't feature any inlet valves. So as they grow, they must create a larger and larger vacuum inside themselves; and the outer air pressure on their skins must increase. If they grow large enough, surely the stalks will snap off the bushes and the peppers will float... show more
    Bell peppers (and chilli peppers) are hollow but they are hermetically sealed and don't feature any inlet valves. So as they grow, they must create a larger and larger vacuum inside themselves; and the outer air pressure on their skins must increase. If they grow large enough, surely the stalks will snap off the bushes and the peppers will float up into space? Does this ever happen?
    3 answers · Botany · 8 years ago
  • What is the best way to turn my paintings into greetings cards?

    I want to reproduce my acrylic paintings as cards, but I don't know much about printing techniques. If anyone can suggest a good, reliable (and hopefully cheap!) method that doesn't destroy or damage the painting I will be very grateful!
    I want to reproduce my acrylic paintings as cards, but I don't know much about printing techniques. If anyone can suggest a good, reliable (and hopefully cheap!) method that doesn't destroy or damage the painting I will be very grateful!
    3 answers · Painting · 8 years ago
  • Where does the illumination for dreams come from?

    How are we able to see in dreams (bearing in mind that it's dark at night and we have our eyes closed)? If the illumination comes from our 'imagination', why can't we use our imagination in waking life to illuminate dark rooms, thus saving on light-bulbs?
    How are we able to see in dreams (bearing in mind that it's dark at night and we have our eyes closed)? If the illumination comes from our 'imagination', why can't we use our imagination in waking life to illuminate dark rooms, thus saving on light-bulbs?
    5 answers · Biology · 9 years ago