Questions tagged [everyday-life]
Concerns the application of the laws of physics to analyze common situations encountered in everyday life.
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Would wearing clothing that is black on the inside and white on the outside keep you cooler?
The Straight Dope ran an explanation of why nomads often wear black clothing - it absorbs heat better from the body. On the other hand, white clothing reflects sunlight better. Is it possible to get ...
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Why is the shape of lightning or an electric spark a zig-zag line?
Why is the shape of the lightning (or an electric spark) always of a zig-zag nature? Why is it never just a straight line?
Image source.
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Why do different letters sound different?
If one sings the letter "A" and "M" at the same volume and pitch, the two letters are still differentiable. If both pitch and volume are the same however, shouldn't the sound be the exact same?
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What happens when we cut objects?
What is the role of the molecular bonds in the process of cutting something? What is the role of the Pauli exclusion principle, responsible for the "hardness" of matter?
Moreover, is all the energy ...
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Why does water fall sort of helically from a cup? [duplicate]
I noticed today that if I took a glass of water and poured it out slowly (small tilt to the cup), it flowed rather smoothly, but when I increased the tilt the water flowed in a sort of helical manner, ...
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Wavy stream of liquid
While pouring a liquid into a glass from a bottle, some streams have a wavy shape, like the one in the following photo:
What causes the stream to be of such a shape?
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Should I heat my room when I'm not here, energy-efficiently speaking?
I was wondering as it's getting cold : is it better for my electricity bill to shut down completely my (electric) heater during day, and to turn it on again when I come home (then it will have to heat ...
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How do candles and wicks work?
The wick of my tea candle was buried in wax. So I lit a piece of paper and stuck it in the wax. Now the wax is burning off the paper, as if that were the wick.
The wax itself wouldn't light on fire ...
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Opening the fridge door to cool a room
I'm well aware that the default answer to this textbook default question is "it doesn't work", but still, I believe it does.
To cool the insides of the fridge, the compressor must do work, and since ...
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Why does a breeze of wind make us feel cooler? [duplicate]
In my Astronomy class, I learned that temperature results from the speed of air molecules colliding into your skin. Thus, if the air molecules in the room have a high kinetic energy and thus collide ...
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Why the pressure of atmosphere doesn't crush you when you e.g. walk outside?
Why the pressure of atmosphere doesn't crush you when you e.g. walk outside? I mean the density of air is $1.26 kg/m^3$, so with $100 km$ above us, it exerts much pressure on you when you walk outside....
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Why is oil a better lubricant than water?
How come mineral oil is a better lubricant than water, even though water has a lower viscosity?
When two surfaces slide over each other with a gap filled with a fluid, the different layers of the ...
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Why does a candle blow out when we blow on it? Our breath is 16% oxygen and only 4% CO2
Don't say that a layer of carbon dioxide covers the flame, because our breath has more oxygen than carbon dioxide.
Also, our breath does not extinguish the flame by cooling it as it is itself warmer ...
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Why do power lines buzz?
When near high tension power lines, particularly after a good rain, the lines themselves emit a buzzing noise. A similar noise can be heard coming out of the electric meters attached to my apartment.
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Why CAN we see the new moon at night?
I understand that the Moon's phases are determined by its position in orbit relative to the Sun. (See: Full Story on the Moon). The "shadow" is not cast by the Earth (a common misconception - this is ...
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