Questions tagged [experimental-physics]
For questions about design, process, data, or analysis of experiments and observations.
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On the Rømer experiments and the speed of light
In 1676, Rømer determined that the speed of light must be finite.
His experiment consisted on observing the eclipses of Io, one of Jupiter's moons, by Jupiter itself. He timed these eclipses over a ...
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Is there any full Compton scattering experiment done with x-ray since 1923?
The original paper of A.H.Compton 1923 did not provide data of a full experiment; he provided 3 points. Was his result corroborated by others?
Can someone provide a real full set of data for Compton ...
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Do fractal objects exist in the real world?
I'm talking about a fractal in terms of Hausdorff or Minkowski–Bouligand dimension.
Thinking about the Chaos Theory for a while, I have a question about real-world fractals.
I've found appropriate ...
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Is it possible to calculate pressure without a barometer?
For an experiment, I need to pump air into a rocket with varying volumes of water, and thus air. However, I want to keep the pressure the same. Given the amount of air a bicycle pump can pump, the ...
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Time of detection for single-electron double-slit experiment
Consider the single-electron double-slit setup, where an electron gun fires a single electron, and a dot is observed on the detector screen behind the slits. We do not place any detector in the slits.
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Why does the ion and electron currents saturate in Langmuir probes?
From the I-V characteristics of the Langmuir probes used in Plasma diagnostics, we can calculate the plasma density, temperature, etc from the ion and electron saturation currents. But why does the ...
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How to compute the curl of the electric field, experimentally?
In order to experimentally verify Faraday's law and express the curl of the induced electric field, is there any other way to compute the curl without directly working on the cross product (ie working ...
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Is it possible to “force” two separate light sources to be coherent?
I have edited this question for three reasons. They are:
1. A possible duplicate of another question. (I believe the "answer" to that question is incorrect.)
2. I received two contradictory answers.
3....
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Investigating the relationship between a changing B field and the curl of the electric field induced
I am currently working on a 12 page lab report on Faraday's law, essentially investigating, how for different magnetic field strength through a stationary loop of wire with N number of turns, effects ...
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How did Newton know gravity force between 2 objects although he could not examine it?
Yes, Isaac Newton calculated it, I know.
But he could not examine the force between 2 objects (for example apple and human hand). And we all know there is gravity force between every 2 objects even ...
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Grad student needing help with a fluid mechanics issue in project
As the subject states I have hit a wall in a fluid mechanics associated problem in designing an experiment for my grad project.
Long story short, I'm an engineering undergrad who got a broad ...
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$CO_2$ heating experiment (high school)
A student is trying to run some experiments for a project to explore how the concentration of CO2 affects the temperature of air. For this, she:
Drops different ammounts of dry ice (between 0 and 2....
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How to increase Sensitivity and precision of a measuring sensor?
Considering the definition that
Sensitivity: Relation between the maximum of range, the sensor can $\frac{i}{p}$ to the corresponding $\frac{o}{p}$ given by the sensor due to it.
Ex: A pressure ...
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mathematical relationship between height of drop and horizontal splash distance [duplicate]
I was just curious as I am still quite confused, if we vary the height of the ball when dropping it in a pool of water, is there a way to establish some mathematical relationship between the height of ...
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Are my voltmeter readings expected for a correct chua's circuit?
I am following this article Robust OP Amp Realization of Chua's Circuit by Kennedy to implement a Chua's circuit. I use exactly the same design as the article; the only difference is that I use a 15mH ...
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How Do Scientists Measure Subatomic Particles? [closed]
I'm asking for a list of experiments, machinery, technology and techniques. The only measuring device I really know of is the Stern-Gerlach contraption. Google hasn't been helpful (it only gives me ...
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Vacuum test in the laboratory
If I put some water in a plastic container and apply a vacuum pressure of -0.20bar the water comes out of plastic container which should not as per design and material of container. This is called ...
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Is possible to create black hole in laboratory? [duplicate]
Recently I came to know that black hole are the object which concentrate large amount of mass in small volume. what are the requirements to create this if possible?
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Uncertainty in length measurement
I am trying to measure the length and the uncertainty in length of a fiber optic cable for measuring the speed of light. So far, I have measured it the standard way: Using a standard meter scale. I ...
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Has the Michelson-Morley experiment been performed while moving in relationship to Earth?
I'm currently trying to debunk some geocentrist claims the Michelson-Morley experiment proves Earth isn't moving and I'm wondering - has this experiment ever been performed while in motion relative to ...
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Evolution of theories in physics [closed]
I am searching for a book on the theories of (high energy) physics to gain insight, why they are so powerful.
Namely, I would like to find a book that uses the evolution of physics from classical ...
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Constant Acceleration and Displacement
How can I conduct an experiment to show that the area under a velocity-time graph equals the displacement when the velocity is changing at a constant rate? I've tried to measure free falling objects, ...
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Why small amount of water in glass, moves along it's walls?
Many times I had noticed that when a small amount of water is left in glass, it always stays sticking to it's walls, whenever I move the glass, most of the water moves along the glass's walls. I think ...
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Momentum of neutral particles in particle colliders
I understand that we can find a momentum (or a charge to momentum ratio anyhow) for a charged particle (charge $q$) in the LHC by using it's radius of curvature $r$ as
$$\frac{mv}{q} = Br$$
So that ...
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Tianqin project vs LISA
How does Tianqin space-based gravitational wave detector compare to LISA? Will it be able to detect gravitational waves from e.g. inflation (considering possible upgrades)?
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How the field profile is in a diagonal end of the optical fiber?
I would like to know how is the propogation of the beam, let's say Gaussian beam profile, in the end of the fiber? Does it go in shift to the lower side? Does it change its shape? And how the near ...
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Is there a way to see the sun's outer layers from earth outside a solar eclipse using polarization?
¿Is there a way to filter sky light using light polarization?
in https://en.wikipedia.org/wiki/Coronagraph#Invention it says:
High Altitude Observatory's Mark IV Coronagraph on top of Mauna Loa, use ...
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Experimental time-series for quantum particle-in-a-box or simple harmonic oscillator?
I would like to see experimental results for repeated measurement of a single-particle, quantum system that is approximately either particle-in-a-box or simple harmonic oscillator. If particle-in-a-...
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How do we determine that an object is neutral?
This has been bothering me for a while. Imagine that you are an experimentalist who does not have any known mass or charge to compare against. Imagine also that you do not have any idea about the ...
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Empirical determination of masses and charges of a set of objects using only kinematics experiments
Suppose you have $n$ physical objects that you want to determine the mass and charge of. You do not have access to any reference object with known mass and charge (that also includes things like the ...
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Do metallic meshes work in practice as thermal radiation shields?
The other day I was thinking about the wire mesh cover used in microwaves to keep the microwave radiation inside cooking your food. The idea is that the spacing of the mesh is much smaller than the ...
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Measuring signal shorter than instrument response function
If one has a well-defined instrument response function (IRF) of some known full-width half maximum (FWHM), and they are measuring a signal that is shorter (but the shape is known), is it possible to ...
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How do measurements of $G$ account for variations in the local gravitational field?
One of the notable discrepancies of modern physics is the current disagreement of measurements of the gravitational constant $G$, well beyond reported uncertainties (and agreeing only to about 1 part ...
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Why are measurements and calculations of atomic radii so different?
On Wikipedia, the 'empirically-measured atomic radius' is smaller for most of the elements on the 'atomic radius' page than it is on the pages of the individual elements. Why?
The measurements on the ...
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How to measure flow rate using Toricelli's law?
For my experiment, I want to investigate the relation between height and velocity using Torricelli's law. I would like to know how I would measure the flow rate from volume in a spouting cylinder.
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Experimental Physics - Defining convolution in terms of equipment resolution
So I think this video:
https://www.youtube.com/watch?v=N-zd-T17uiE&t=67s
By Faculty of Khan does a wonderful job in explaining what convolutions are. We basically consider two pulses $f(\tau)$ ...
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Propagation of Uncertainty vs Dividing Uncertainties
I have a quick question!
When I’m calculating the uncertainty of a formula, like $v = d/t$ . . . What method do I use? Sticking with my example ($v = d/t$).
Do I convert the uncertainties of ...
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How to determine the focal length of a combination of two convex lenses separated by a distance $d$ experimentally without formula?
I have done this experiment to find out the equivalent focal length of a combination of 2 convex lenses of slightly different focal length and have applied the formula for the equivalent focal length ...
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Should the electrical charge of $\pi^+$ (positive pion) be considered exact?
According to https://en.wikipedia.org/wiki/Elementary_charge, IIUC, electrical charge of an electron should be considered an exact value of 1.602176634 coulombs instead of an experimental value with ...
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Projecting double slit onto fog instead of screen [duplicate]
In the quantum mechanical double slit experiment, the resulting pattern is projected onto a screen. This is an important part of the experiment, because the screen represents the quantum mechanical ...
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Laser power inside a vapour cell
I have a laser beam whose power I measured to be x $\text{mW/cm}^2$. Furthermore, I measured the beam profile of the laser beam and therefore can estimate its intensity. I shine this laser through a ...
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Experimental methods to identify C.O.G of a highly heterogeneous cube
While taking to a college about calculating the centre of gravity of multibody basic objects, the question was raised on how one would determine the C.O.G of a highly heterogeneous object of a given ...
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How many realm are there in physics? [closed]
I remember back in middle school, learnt physics in a few large categories:
1) force (kinetics) 2) heat 3) optical 4) electrics 5) atom physics
is it still valid or is it categorized by different ...
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Horizontal splash distance of water
I just want to know, can we somehow derive an expression for the splash distance of water (horizontally) if we drop a ball in to a pool of water and aim to measure the maximum distance the water has ...
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Identify reasons for laser intensity fluctuation
I got a Mitsubishi LPC-826 laser diode (single mode) with laser driver iC-HG. There is no cooling device, but data was captured after 30 mins switching on (which should be temporally stable). The beam ...
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An error in a physics documentary?
I was watching
The Amazing World Of Gravity (Full Physics Documentary) | Spark
on Youtube, and I didn't quite understand a certain part. From 5:00 to 9:00, Professor Jim Al-Khalili was recreating ...
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Is there any advantage when using magnetic stirring vs the common grinding?
Is there any advantage when using magnetic stirring vs the common grinding?? In terms of the shearing forces applied on over the sample and its degradation
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Doubts on conductor and insulator
I read on Stephen Gray's discovery of conductor and insulator. From that I came across a question that how cork, wood, rope can act as conductor being an insulator but then I got the answer that it is ...
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Why are soft photons considered undetectable?
Wikipedia says that soft photons are undetectable. Yet, single photon counters exist for visible photons with relatively high quantum efficiency. So why can’t one set up an experiment to detect ...
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Why infrared laser goggle looked orange?
So here's the thing, the laser goggle for UV light looked orange-yellow, which was sort of understandable, cause, if one want to block UV light, then the transmitted light ought to stay away from the ...
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