Questions tagged [physics]
A puzzle relating to physics equations or physical principles such as energy, entropy, and classical/quantum mechanics.
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A quantum physics puzzle [closed]
A new mathematical approach to quantum physics via graphs was found recently, see this paper for more details. It particular, it refers to
papers by Anton Zeilinger, a Nobel laureate in physics of ...
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Visual puzzle with a grid
Puzzle I composed, the reasoning matters more than the correct answer.
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a11eN756e64657261747461636b
Note: if it isn't obvious, none of the below or any of the decrypted message are intended to be real.
C:\TopSecret\vacant\alien_transmission.jpg:
...
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5
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Move a coin without touching it
There are three coins lying flat on a table, arranged in a straight line with their edges touching. Call the coins A, B, and C (B is in the middle). Here are the rules:
You can touch and move only ...
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4
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Elapsed International Power
Clues: [contextual images] [beefcake horse] [beefcake horse reversed with 261] [x10]
Instructions: Name That Movie
_ _ _ _ T _ _ _ _ _ _ T _ _ _
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Centridipity problem
Two objects are fixed inside a moving car by strings so that they can both move freely.
The car's windows are closed.
A wind chime is suspended from the roof.
A helium balloon is tethered to the ...
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2
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1
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Decode this signal from outer space
A light signal is received from outer space at a frequency of 982.002MHz
Calculate the wavelength of the signal and identify a corresponding earth unit.
By using the exact value of the unit convert ...
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Circuissonne Diagrams
This puzzle is part of the Monthly Topic Challenge #7: Board games.
And also, this puzzle is also a parody of XKCD's 730.
We're starting a project on Explain XKCD (link currently not available) to ...
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Which ball will finish faster? [closed]
I release two identical balls down these two ramps. Which ball will finish faster and why? There are no hidden tricks and this is a pure physics question.
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DCQ Pencil Top - a Quantum Enigmatic Puzzle
Clues: SILNZEANGIA ESEPCZUANGIA
[Contextual Image]
Instructions: Name That Place
_ _ _ _ a _ _ _
Hint:
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10
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3
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Catching the "L" train
This is a more difficult version of an earlier puzzle.
Hit the "C" ball at such an angle that it creates a chain reaction which ultimately dislodges the "L" ball.
Whenever the ...
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Release the "Q" ball
Hit the "I" ball at such an angle that it creates a chain reaction which ultimately dislodges the "Q" ball.
Whenever the ball in motion hits a stationary ball, the ball in motion ...
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How fast do you need to run to catch the bus?
You are running to catch a bus that is going on a horizontal road.
The bus is at point (0,0) while you are at point (s,k) where s and k are constants. The bus moves at some velocity v and you have to ...
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Is it possible that pulling the rope with one hand would be easier than with two hands?
I bumped into this interesting question while looking for a fun mechanical black-box puzzle:
Pulling the rope with one hand is as heavy as with two hands?
I wonder if it is possible to generalize this ...
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The Resistor Game Show
You were one of $n$ contestants chosen to participate in a game show. Each of you will secretly select a resistor of your choice, with a resistance between 0.01 and 10,000,000 ohms. Once everyone has ...
2
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1
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3 snails on a triangle. When will they all approach one another?
There are 3 snails at the vertices of an equilateral triangle of side length L.
Snail 1 crawls towards snail 2, snail 2 towards 3, and 3 towards 1. All snails crawl at the constant speed V.
If they ...
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a Heartbroken riddle
Someone broke my heart,
Part of me resides in the intersection of Rand al'Thor and the 26
Sometimes I just need every way of knowing who the fourth to win a race was.
Then again sometimes I just run ...
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The three door puzzle [closed]
In a long room are three doors. Behind each door one block is hanging from the ceiling. Behind the first door the block is made of concrete; behind the second door the block is made of hardwood; ...
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Make an equation from expression "1 4 9 100" [closed]
Fill the gaps of the expression $1$ $4$ $9$ $100$ with mathematical operations $+,-,*,/$, physical units and an $=$ sign, such that a correct equation is created.
Example: expression $1$ $100$ $...
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21
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1
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Quartum non datur
Can you give a good rational approximation of
$$\sqrt[3]2 \times \sqrt[4]2$$
without doing any significant maths?
Hint:
Attribution: Mine.
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22
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11
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Why is the pavement wet?
Saw this the other day. So I took this picture. There was another nearly identical wet patch 2 spaces away.
Why is the pavement wet?
Note: This is a straight forward physics puzzle. This is a ...
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Balancing a yardstick
There is a known trick to this, so “no computers” may be used to look up the answer.
Alice gives Bob a wooden yardstick with a small weight secured to one end and says, “See if you can find the ...
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A Simple (High School Science) Question
Let's say you have a pot with some water in it (as shown). Then you take an empty glass and put it upside down (its mouth on the flat pot bottom) in the pot. What can happen with this experiment?
Four ...
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A very familiar object
I'm sure you all have held a common retractable, spring-loaded pen at least once, and that many of you have tried to make it jump vertically by first pushing it downward against a table to load the ...
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Scientifically Themed Dingbat/Rebus Puzzles - Part 5
Previous ones here: part 1 part 2 part 3 part 4
To reiterate, the media is reasonably well known, so if something has barely any views on YouTube, for example, it's probably not the intended answer. ...
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Scientifically Themed Rebus/Dingbat Puzzles - Part 4
The same basic idea (I have a lot of these): science-styled expressions that represent some popular media. Previously, some guesses were for things I would say aren't that well known, so keep in mind ...
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Scientifically Themed Rebus/Dingbats - Part 3
The same idea as before: the "scientific" expressions represent some form of popular media. Enjoy. Part 1 Part 2
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Can anyone help poor Fblthp?
my name is Fblthp, and I am completely lost.
I don't know the location of my home planet, and given the barriers in language and culture, I can't tell you its name in any meaningful manner either.
The ...
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Scientifically Themed Rebus/Dingbat Puzzles - Part 2
below are more rebuses with "scientific" expressions that represent something in popular media. Part 1 here. One of the questions in Part 1 has a link to a question here.
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Scientifically Themed Rebus/Dingbat Puzzles
Below I have created a list of a few "scientific" expressions that represent some form of popular media, with the type stated. Hope you enjoy.
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Triangular pool and three swimmers [closed]
Given a triangular pool 100, 120, 140 yards and three swimmers which swims at rates of 3.5, 4.0, 4.5 yards per second - place them on the edges of the pool in such way that when they start swimming at ...
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How Do You Prove That This Puzzle Is Physically Solvable?
https://www.reddit.com/r/BeAmazed/comments/fyt7x9/it_seems_to_be_impossible_but_it_gets_done/?ref=share&ref_source=link
The goal of the puzzle is to remove the wooden stick from the jar by ...
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Unused By Only Three
First, beg for the most positive among the stables.
Now you can do the second, beg for the independent.
Now you can do the third, beg for the overlappable.
Now you can do the fourth, beg for the ...
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Two Cannons - A Beginner's Physics Puzzle
Standoff
Let's say we have two cannons aimed directly at one another ( as my horrible attempt shown in the image ).
The Angles
The cannon on top is aiming down towards the one on bottom right, and ...
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Three mini-crosswords with maths/physics theme
Three mini-crosswords are presented below. There is a maths/physics theme to these puzzles.
I am sure that they will be solved quite quickly and hints will not be required, but if anyone gets really ...
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Clever Collision Counting
A mass of 1,000,000kg is sliding in from the right on a friction-free, level surface.
It has a perfectly elastic collision (collision 1) with a stationary 1kg mass.
To the left of the 1kg mass is a ...
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You can see me but you see through me
This is my second (easy) riddle:
You can see me but you see through me.
I can fill the room but I will vanish as soon as nobody creates me.
I transport energy but I am not sure if I am made of ...
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If the second hand goes backwards, starting from 12:00, how long does it take to meet with the minute hand?
If the second hand of a clock goes backwards, starting from 12:00, how long does it take until it meets with the minute hand (which is going forwards)?
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Traffic lights in space
In a distant future, human beings are travelling between planets and even solar systems with ease. Their advanced technology allows them to drive their own space-cars, which have a cruising speed of ...
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The falling broom handle
As the reaction to my previous physics puzzle was somewhat mixed, I'll try again. I found this in an online physics book.
You hold a broom as shown in the following picture:
The head of the broom is ...
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A pencil in a beaker of water
You have a beaker containing 100ml of (slightly salty) water, standing on a digital scale. The scale has been calibrated to the beaker so that it shows only the weight of the water, which is exactly ...
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Distance between two friends [closed]
Two friends are 200 meters apart in a concourse. They then both walk 100 meters each with their faces towards to each other. Yet after this 100 meter walk they are still 200 meters apart.
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Run to a point in a triangle in shortest time [closed]
This is a generalization of a puzzle that dealt with an equilateral triangle.
Assume three runners with the following speeds - 4.5, 6.2, and 8.7 meters/sec. They are at the corners of a triangle with ...
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Two Identical Pistols Shot Simultaneously [closed]
Two identical pistols are shot at the same moment, one in Death Valley and the other the Schwarzwald Germany. Both of them are at targets 40 meters away. Which one hits its target earlier?
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Pulling the rope with one hand is as heavy as with two hands?
There is this box, having two holes, and the ropes going through each of them.
I try to pull the left rope with my left hand... And it's heavy...
Then I try to pull the right rope with my right hand......
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How many times does the earth rotate per year?
Assuming there are exactly 365 days per year, how many rotations about its axis does the earth make in one year?
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Who is our nearest planetary neighbor, on average?
Assume that the planets have circular orbits centered on the sun. Assume that the radius of the orbits is 0.39, 0.723, 1, and 1.524 for Mercury, Venus, Earth, and Mars.
Assume also that there are no ...
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Is it Basic Physics?
Which number is next in the sequence?
1, 2, 3, 4, 5, 6, 7, 9, 10 ,11 ,12 ,13 ,14 ,15 ...
Describe why and how your answer applies to the given problem.
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Is it possible to determine the original direction of water flow? [closed]
Take two beakers of water and use a spoon to stir water clockwise in one beaker and counterclockwise in the other beaker. Observe the beakers after a sufficiently long time when the water flow has ...
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Pucks in the arena
Two identical pucks of radius 10 cm are placed in a round arena of radius 1 m. They are positioned 50 cm away from the center of the arena on opposing sides. Assuming no energy losses during sliding ...
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