Concerns the application of the laws of physics to analyze common situations encountered in everyday life.
Questions tagged [everyday-life]
2216 questions
63
votes
3 answers
Why do the big nuts always remain at top? The Brazil-nut Effect
Most of the time when I mixed different nuts in a bowl, I observed that the big Brazil nuts were always on top while the small peanuts settled near the base. No matter how you take it, if the big nuts are put at the bottom and then the small nuts…
user36790
43
votes
2 answers
Why do stickers curl?
When peeling a sticker off its base, the immediate reaction is that it curls; why is this? I am having trouble finding an answer to this. Could it be that the glued side expands upon contact with the air? And, on a somewhat related note, is this a…
K. 622
- 787
21
votes
5 answers
Why do books have dog ears?
I googled the question and found no explanation. It seems that dog ears are inevitable (for paperbacks, notably) even if you've always been careful. From my experience, they are about equally likely to appear on the top corners as on the bottom…
Eric
- 831
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16
votes
4 answers
Why is it that when a chalk board gets cleaned, the area that used to have chalk is the cleanest?
Why is it that when you erase a chalk board, the area where the chalk used to be becomes the cleanest? By that I mean that when you erase a chalk drawing, the board gets smeared with chalk dust, but the area where the drawing used to be has less…
Shep Bryan
- 365
8
votes
8 answers
Why won't my door close in the winter?
Please, take this question seriously, because this is a real problem to me. I have a door in my flat. A closet door, to be specific. And there is a problem with it.
In the summer everything is ok, the standard wood door opens and closes as…
Dan Ganiev
- 191
8
votes
2 answers
How does varying temperature affect the accuracy of grandma's pendulum clock?
I have an antique pendulum clock(my granny's!) . If I detail it,
This clock is approximately 5 feet tall and enclosed by wood and below it its glorious pendulum oscillates .
It gave more or less correct time. But then I saw it was going slowly . I…
user36790
7
votes
4 answers
How does "pushing-start" a dead-battery manual car work?
A few days ago the battery of my car went (almost) dead. As it is a manual car, my father once told me that the way to get it going without jumper cables was to push it or let it roll down a hill, sink the clutch, shift to 2nd gear and then let go…
Cal Gibson
- 429
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7
votes
1 answer
Why does penne pasta go into rigatoni during cooking?
I was boiling penne and rigatoni pasta in the same pot (both are hollow cylindrical pasta of approximately the same length, but rigatoni has a noticeably larger diameter) and almost all of the penne pasta managed to find its way inside one of the…
user3308082
- 256
7
votes
2 answers
Why is it so hard to mix spaghetti with meatballs?
When I cook spaghetti with a sauce that includes meatballs or chopped vegetables, those stay in chunks and won't get uniformly mixed in the pasta.
Is there a simple reason for that?
Has it been studied? you know some people study piles of sand with…
fffred
- 4,266
6
votes
1 answer
About pizza cutters and straight knives
I saw this question on another site. It asked if a pizza cutter could cut fabric. which is not what I ask. A pizza cutter stays stationary wrt the underground while a straight knife moves. In both cases, though you can exert the same pressure. So…
6
votes
1 answer
Does pencil lead have a direction?
If I understand correctly, graphite is made of sheets of carbon.
(from Wikipedia)
And when I write with a pencil, sheets of carbon slide off the end of the lead. Does that mean there is an optimal orientation of the graphite where the sheets are…
jkd
- 163
6
votes
1 answer
Is the Sun dusting my electronics?
I recently noticed this odd dust formation on my gaming console's camera peripheral. The dust is significantly thicker on the right side, with the television in the background. On the left, with a West-facing window in the background, there is very…
Sam
- 199
5
votes
5 answers
Why is it easier to walk diagonally upstairs
Try it yourself on a set of wide steps! Work is given by
$$\int_C \mathbf{F} \cdot d\mathbf{x}$$ where $C$ is a path integral. In this case I think $\mathbf{F}$ is a rotational vector field because the stairs are essentially a set of…
ldog
- 151
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5
votes
1 answer
Why do baked goods "fall" if exposed to sudden cooler air?
This is a know rule when baking:
Don't open the oven until your cake is finished, otherwise it will "fall".
Why/how does this happen?
Petr
- 3,069
5
votes
2 answers
Why does my rear window defogger remove rain?
I've noticed this before and still don't have a picture, but...
Today it was lightly raining in the morning. As always, I turned on the rear defogger. I do this because I have noticed it clears the water from the rear window.
It takes maybe a minute…
Maury Markowitz
- 8,201