Questions tagged [everyday-life]
Concerns the application of the laws of physics to analyze common situations encountered in everyday life.
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A Hotwheels Problem [duplicate]
I have a Hotwheels track set. It has a looped structure such that at some point in the car's trajectory, it becomes upside down. But in such a situation, it doesn't fall to the ground. I understand ...
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Frost on my windshield at 40° f on a clear cold still morning?
I LOVE this question/idea. So, how many different kinds of heating and cooling are there? If the "radiative" cooling or temperature of a clear night sky can be minus 60, how come I'm not ...
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Why does a plastic bag rip when it is raised to a higher position when being held but not when it is stationary?
Let me preface this by saying I am not a physics expert, but this is something I was wondering and I would love a technical explanation.
For example, say you're walking with an filled plastic grocery ...
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In depth answer: Why do I see sparks when I remove synthetic clothes off my body?
I have combed through various sources on the internet and I don't have a definitive answer for the above question:
The best that I can come think is the following:
Because when I remove synthetic ...
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What happens if you're sitting in a wheelchair and you turn only one wheel?
My friend was sitting in a wheelchair, with a cup of coffee in one hand. That made me wonder, how would the wheelchair move if he turned only one rear wheel?
He tried it, using his right hand to turn ...
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Steam from a cup of coffee
I observed that, in winter there is more visible steam from a cup of coffee than in summer. Is there any phenomenon taking place here.
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Why there is water produced on the phone if we keep our phone in our pocket for a longer time?
one day I kept my phone in my pant pocket, I haven't opened it for a long time. My phone is covered with a plastic case. So why the phone is getting wet when I observed it after some time even though ...
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An egg gets soft before it gets hard [closed]
I found in a book from 1500's that says that when you cook an egg (I assume a raw egg), it will get softer before it gets harder. Is that accepted by the science community today? Can someone explain ...
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Does opening both windows in a room cool the room twice as fast?
It's getting colder where I live (~40 degrees Fahrenheit). The place where I live (college dormitories) pumps the heat up into the 80's, so I keep the windows open most of the time. I noticed that, ...
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Why do water particles appear to be exiting a stream of water from a faucet, instead of the stream being held together by surface tension?
I recently noticed an interesting phenomenon while watching the tap running in my kitchen. At the time, there was bright sunlight coming in the kitchen window. As the stream was running out of the tap ...
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Why image of high-altitude clouds is formed in a shallow lake? [closed]
Suppose we look at the surface of a lake and see a reflected image of high-altitude clouds in the sky. The distance of a cloud from the lake is far more than the depth of lake. So then how can an ...
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What causes the curvy line to exist? [duplicate]
Excuse me, but I am wondering what optical phenomena causes the curvy line to exist on the iron fence?
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Why does the bottle create vacuum inside if left closed?
I'm not 100% it's correct but it has happened to me a lot of times, I always close down a bottle normally with not too much tightness, with no liquid inside, and after a day it always is so hard to ...
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Does food stay hotter if you keep air in the bag?
If I am taking takeout home in a plastic bag, is it better to remove all air from the bag when sealing it so no heat is lost to the surrounding air or keep air in the bag acting effectively like ...
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Will hot object near ceiling vent create more draft? [closed]
As in the picture, we have a room with vents at the bottom to let cold air in and at the top to let hot air out. Normally the air flow is limited by the temperature gradient (correct me if I'm wrong). ...
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How are bubbles formed when a raindrop hits a flat pool of water?
I have noticed that raindrop impact can create a bubble on the surface of the water in a hot tub (104°F) up to several centimeters in diameter that is stable for several seconds before bursting.
The ...
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What are natural retro-reflectors?
Recently I was on an airplane on a sunny day. The sun was shining on the other side of the plane and noticed a bright patch on the ground following beside us. Eventually I noticed a dark centre to ...
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Why are my ice cubes sticking in their containers?
I make my ice in those little round to-go containers that usually hold sauces/dressings.
When using the clear containers, the ice sticks to it and requires heat or violence to get it out. When I use ...
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Help understanding quote on theory and knowledge in Gravitation (Misner, Wheeler, & Thorne, 2017)
I came across an interesting discussion at the start of chapter 3 of MWT Gravitation. It reads:
Here and elsewhere in science, as stressed not least by Henri Poincare, that view is out of date which ...
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Why is it more difficult to turn the steering wheel of a stationary car than a moving car? [duplicate]
I believe anyone who has driven a car without power steering has noticed this effect. I am not able to find a justifiable argument online. My thought process suggested it must have to do something ...
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How might one produce a glory -- a circular rainbow -- in crystal?
A glory is the technical name for a full circle rainbow, such as is sometimes (but rarely) seen from below above a waterfall, or below from above a cloud. I am asking this question here. because it ...
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Why does a shadow of a fork 'dissappear' once submerged? [duplicate]
NO SHADOW of the fork!
A distinct black shadow can be observed at the bottom of a glass before and after the fork enters the water, but the shadow disappears at the instant of entry, is this a ...
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Why is the coefficient of static friction used in the formula for the stopping distance when there is no relative motion between tyres and road?
Instead of using the coefficient of static friction between the tyres and the road, should we not use the coefficient of kinetic friction between the brake pads and the disc?
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Why adding weight to a motorcycle increases the stoppage distance?
I was doing my car license's questions, and it came up this question, why would the stoppage distance (the distance which the car stops after breaking) increase if you add more weight on top of the ...
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Gravity vs adhesion of a water droplet
How much volume can a water droplet that is attached to a vertical glass surface have before it begins to roll downwards?
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Why do headphone speakers sound 'tinny' when far from the ear?
For me it is counter-intuitive: I should be hearing more low frequency sounds (bass) at a greater distance from a headphone speaker (like I hear only the bass when standing outside a club), because ...
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If energy is conserved, why do we need to save energy?
The conservation of energy says that it can neither be created nor be destroyed, it can only be transferred from one form to another. i had this doubt in my mind for a long time that why do we need to ...
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Why does dew only fall on horizontal surfaces?
I noticed that dew only falls on horizontal surfaces, while vertical surfaces remain dry.
But dew is the condensation of water vapor contained in the air. And for the condensation process, the ...
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Will a mass $m$ rotating around a black hole with mass $M$ form a new black hole together with $M$, at a close enough distance?
A mass $m$ rotates around a black hole with mass $M$ at a distance $r$ from the horizon. The combined system has an energy depending on the mass $M$ and the rest energy and kinetic energy of $m$.
When ...
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In beer, why do bubbles travel faster upwards in the center?
This is a very odd question, but I just so happened to be observing a pint of beer and realized that the bubbles floating up seemed to travel faster towards the center of the glass than towards the ...
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Why do dry lentils cluster around air bubbles?
When I pour dry lentils into a water bowl, I notice many of them form little clusters, with an air bubble in the center.
Why does this happen? I'm guessing something about static electricity. But not ...
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Why a car stops slower when you press the brake pedal fully rather than progressively?
I have always been told that if you press the brake pedal fully and fast it can make the wheels lock themselves, and that you shouldn't do so because it would take longer to stop the car than if you ...
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Why do spheres indented by a curve follow the curve when later rolled on the same curve?
In this Youtube Short it was mentioned a way of constructing a shape that followings any curve one could draw. Apparently the motivation to construct it is to do the following, roll a sphere of clay ...
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Why do we move the spoon in a plate to cool it down?
Say we have a plate full of soup, why to cool it down we move the spoon around in the plate? Is it to facilitate the thermal interchange between the air and the soup? Also why is the edge of the plate ...
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Why does water come out of a bottle in waves?
So imagine you have a bottle of water or any type of liquid (like a bottle of milk that has just been opened)that is completely full or even three quarter of it is full,why does the water or milk come ...
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How does a violin produce notes, microscopically?
I believe this question would have been asked before, but not like this. The popular answer to this question is that the slide-release action of a bow sets up vibrations in the strings, of which ...
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Why don't bike wheels behave like a gyroscope when you turn them?
Let's say we have a bike pointing forward in the $+z$ direction into the screen. It's moving in the $+z$ direction hence the wheels have angular momentum in the -x direction ,which is towards the left ...
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Why is an arrow pointing through a glass of water only flipped vertically but not horizontally?
Look at the bottom picture for example. If I try to imagine the glass of water as a lens, shouldn't it be flipped in both axes? Why does it only flip in one axis?
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Why front wheel drive (FWD) is physically more stable than rear wheel drive (RWD)?
As generally known, FWD cars are more stable than RWD, but I don't know why and I couldn't find the reason. Can anyone explain me with physics concept?
Additionally, I also want to know why driving ...
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Unexpected rainbow in window
Lately, I observed a rainbow-like ring forming in my window during nighttime when the light enters from a street lamp. Interestingly, the sequence of colors in the rainbow seems to be reversed from ...
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Why does bright objects make less bright objects invisible?
I was walking by the sidewalk during the night when I noticed a swarm of flies circling a street lamp. It was difficult to see at first, so I tried looking in different angles. The security gate came ...
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Why do disk brakes generate "more stopping power" than rim brakes?
Bicycle's brakes generally fall into two broad categories: rim brakes where the braking pads pinch against the wheel's rim, and disk brakes where the pads press against a disk (rotor) that is rigidly ...
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How can you measure the propagation distance of a wave?
Suppose a simple spherically-symmetric cosine wave of wavelength $\lambda$ and velocity $c$ is transmitted from an unknown point outwards in $2D$ (in circles). We'll denote this unknown point as $(0,0)...
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How does a vertical anemometer work?
We know that the vertical anemometer, just like the cup/vane anemometer, works by measuring how fast the cup/fan rotates because of the wind. But how could we possibly know that the fan rotation is ...
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Can you deduce how far lightning struck from you?
This is just a fun with physics type of question. Seeing that both the speed of sound (In air) and the speed of light are a known constant is it possible to measure the amount of time between you ...
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Why is cycling easier while standing on the pedals?
On high slopes and rugged terrains, riding a bicycle while standing on the pedals is easier. Even though I cannot physically define what is "easy"; since it is a feeling that my body ...
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Why does a dump yard stink more in the night?
There was an open dump yard a few miles away from where I used to live for an internship. It was not noticeable during the daytime, but once the sun sets, the dump yard reminded us of its presence ...
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How does an aircraft turn?
Imagine riding a bike on a downhill road to the north, approaching a 90-degree turn. You make a perfect right turn, and your bike now moves east. You then stop and wonder how that is possible. Your ...
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Too fast into a corner: should I brake?
Thought about this during a recent road trip. Suppose I'm driving in a corner and realize I went in too fast, and I'm worried that the tires are about to slide. Should I slow down?
Assume the corner ...
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Why do water sounds different at different levels?
I observed that when we fill a water bottle it sounds different at different levels of height.
means it sounds different while filling at $\frac{1}4$ level and different at $\frac{1}2$.
I just want to ...
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