Questions tagged [everyday-life]
Concerns the application of the laws of physics to analyze common situations encountered in everyday life.
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Given Newton's third law, why are things capable of moving?
Given Newton's third law, why is there motion at all? Should not all forces even themselves out, so nothing moves at all?
When I push a table using my finger, the table applies the same force onto my ...
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Why does holding something up cost energy while no work is being done?
I read the definition of work as
$$W ~=~ \vec{F} \cdot \vec{d}$$
$$\text{ Work = (Force) $\cdot$ (Distance)}.$$
If a book is there on the table, no work is done as no distance is covered. If I ...
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How can magnets be used to pick up pieces of metal when the force from a magnetic field does no work?
I learned that the force from a magnetic field does no work. However I was wondering how magnets can be used to pick up pieces of metal like small paperclips and stuff. I also was wondering how ...
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Does Earth really have two high-tide bulges on opposite sides?
The bit that makes sense – tidal forces
My physics teacher explained that most tidal effect is caused by the Moon rotating around the Earth, and some also by the Sun.
They said that in the Earth - ...
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How does water evaporate if it doesn't boil?
When the sun is out after a rain, I can see what appears to be steam rising off a wooden bridge nearby. I'm pretty sure this is water turning into a gas.
However, I thought water had to reach 100 ...
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Why do wet objects become darker?
When something gets wet, it usually appears darker. This can be observed with soil, sand, cloth, paper, concrete, bricks...
What is the reason for this? How does water soaking into the material ...
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Cooling a cup of coffee with help of a spoon
During breakfast with my colleagues, a question popped into my head:
What is the fastest method to cool a cup of coffee, if your only available instrument is a spoon?
A qualitative answer would be ...
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Why is the return current through a printed circuit board's ground plane concentrated below the circuit trace?
The Wikipedia article on ground plane says
In addition, a ground plane under printed circuit traces [the paths that the circuit currents take] can reduce crosstalk between adjacent traces. When two ...
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Why do shadows from the sun join each other when near enough?
I was laying on my bed, reading a book when the sun shone through the windows on my left. I happened to look at the wall on my right and noticed this very strange effect. The shadow of my elbow, when ...
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Why does a cork float to the side of a glass?
Why does a cork ball float to the side of a glass as illustrated in the following GIF? What is the physical phenomenon behind this observation and why does it happen?
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Is electricity instantaneous?
My question is basically what exactly is electricity? I've simply been told before that it's a flow of electrons, but this seems too basic and doesn't show that electricity is instant. What I mean is ...
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Height of Water 'Splashing'
Suppose from a height $H$, I throw a ball of mass $M$ and radius $R$ with initial velocity $u$ into a pool of depth $x$ having a liquid with density $\rho$ and coefficient of viscosity $\eta$.
Upto ...
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Do low frequency sounds really carry longer distances?
It is a common belief that low frequencies travel longer distances. Indeed, the bass is really what you hear when the neighbor plays his HiFi loud (Woom Woom). Try asking people around, a lot of them ...
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Can I compute the mass of a coin based on the sound of its fall?
The other day, I bumped my bookshelf and a coin fell down. This gave me an idea. Is it possible to compute the mass of a coin, based on the sound emitted when it falls?
I think that there should be a ...
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Why do I see a saddle in this picture of a computer screen?
I am not entirely sure this is an appropriate question for PSE, however since many of you have such diverse backgrounds, I'll give it a shot.
I have noticed that when one takes a picture of a computer,...
