An experiment is a procedure carried out to support or refute a hypothesis. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results. There also exists natural experimental studies.
A child may carry out basic experiments to understand how things fall to the ground, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments can vary from personal and informal natural comparisons (e.g. tasting a range of chocolates to find a favorite), to highly controlled (e.g. tests requiring complex apparatus overseen by many scientists that hope to discover information about subatomic particles). Uses of experiments vary considerably between the natural and human sciences.
Experiments typically include controls, which are designed to minimize the effects of variables other than the single independent variable. This increases the reliability of the results, often through a comparison between control measurements and the other measurements. Scientific controls are a part of the scientific method. Ideally, all variables in an experiment are controlled (accounted for by the control measurements) and none are uncontrolled. In such an experiment, if all controls work as expected, it is possible to conclude that the experiment works as intended, and that results are due to the effect of the tested variables.
Hello there! This is my first post, so I apologise for any faux pas I am about to commit.
I have recently bumped into a few situations where I'm uncertain about my uncertainties. Especially where the value is a product of multiple variables.
Please see the attatched table, where g is a function...
Hello,
I wanted to confirm a suspicion with how the Aimpoint optics work, but to do that I need to do some ray diagrams. I only ever did them with simple convex, concave, and spherical systems while at college.
From what I already know of how reflex sights work, the LED is placed at the focal...
I am having difficulty located experimental or observational proof that a barycenter exists between the Earth and Moon. All I can find seems to just assume that a barycenter exists because the Moon revolves around the Earth based on the assumption that the Earth and Moon are tied as a unit with...
Hi everyone. I've been working as a full time research assistant in an AMO lab for a couple of months and I've found it interesting so far. I'm considering pursuing a PhD in experimental AMO in about a year's time. However, I'm concerned about the non-academia career prospects for AMO PhDs. Is...
I am currently looking to improve my python skills and looking for some projects to do, one which came to mind was experimentally modeling in python. What I like to do is code an experiment say period of a pendulum and then compare the model to some data obtained in the lab, issue is I don't...
Dear users,
The situation I have encountered is a simple statistical comparison of the experimental data, which accepted as correct, with the results obtained via six theoretical models.
In the experimental data, there exist y values corresponding to x values and also the measurement errors of...
I am looking at a paper (ref below) that uses a method to precipitate calcium carbonate on a steel pipe. However, the paper gives no method because the reference it uses is linked to a thesis that has not been released. The setup is below...
Now, I kind of understand that it uses a method of...
I am curious about the historic experimental evidence that lead to Kirchhoff's radiation law. It is easy to take for granted the ubiquitous temperature/wavelength curve that lead Planck to the quantization concept. But I wondered historically how the curve was derived.
To clarify, we...
Homework Statement: Hello, I have to explain using numbers the Zeeman effect for hydrogen and the setup needed. I have done some research and if I'm not wrong, then a magnetic field of 1 Tesla is needed. I have no idea how to achieve that using commercially available products and how to even...
I have a 9th grader who is really excited about modern physics and we're looking for a summer program where he can learn (and have fun learning) at the appropriate level. Most of the summer physics programs we've found are only open to current 11th or 12th graders. The Penn Experimental Physics...
I am torn between computational and experimental condensed matter physics for my PhD. My focus is on low dimensional systems (e.g. electron correlation/transport, broken symmetry at the boundaries). I'm currently in the process of applying for graduate schools, and so far, I've chosen all my...
I’m kind of stuck on this one. I don’t see how we can use the acceleration of an elevator to find anything about the value of g. We can of course get the acceleration of the elevator, but it feels like that would be independent of gravitational strength. I feel like we need the mass or the...
Hi,
I'm currently having an ongoing debate with some teachers regarding a practical for Newton's Second Law. The prac involves a cart attached to some weights via a string on a pulley. The protocol as it stands has students add increasing mass to the end of the string (not changing the mass of...
Hey all,
So I'm about to be a senior at a US school, and likely want to do grad school. I'm posting here because my interests are really sort of disparate and don't really share a theme. I like dynamics, stat mech, doing stuff on computers, and doing stuff with my hands...
Anyway, here's a...
Hi! I'm working on MATLAB code to analyze dat for a specific project, but I'm curious if it could made useful for more general purposes. Here's a bit of background on the project:
I'm an REU student and I was assigned to analyze data for a recently conducted experiment. The experiment took...
...Or even based on logic?
I understand that it is expected that there might be a Universal Speed Limit and that this seems with extremely high probability to coincide with the speed of em transmission in a vacuum.
This is borne out by experimentation and observation.
Are there any other...
Hello everyone. First of all allow me introduce my self briefly. I'm a guy from not that high progressed country of particle physics, and i graduated almost a year ago with degree of a bachelor in physics. I was a top student in my uni and got some prestigious scholarships. Just like many other...
You collect 200 data points, 100 with input ##A## and 100 with input ##A'##.
For all 100 ##A## you get output ##C## and for all 100 ##A'## you get ##C'##.
That's way more than 5 standard deviations, so you're ready to publish...
But not really.
Because what matters is not just that input ##A##...
Hello,
My question is what types of data analysis can I perform on a set of theoretical and experimental results? For example, I have v(x) = cos(x) and I plot my observed data to v(x).
Thanks!
Homework Statement
I got an experimental vertical acceleration of -12 m/s^2 of projectile motion for an experiment I did at home where I just had to throw a ball at around 45 degree to the horizontal up in the air and record it's motion, then analyze the motion via computer software. Obviously...
A team of scientists from China's Institute of Plasma Physics announced this week that plasma in its Experimental Advanced Superconducting Tokamak (EAST) would be ready to begin attempting to generate more energy than it uses, in a world first.
I am dubious about more news that comes out of...
I am worried that I am passionate about physics and yearn for a career in physics(through theoretical physics), and by a career I mean a placement in a prestigious institute and then be part of leading physics, but would that require sacrificing my entire 20s and even 30s or can I can get all...
Hey PF,
In 1 month I am going to start my Bs.c thesis. I already "have" a mentor that is willing to supervise me and a topic. The topic is Bohmian Mechanics. I know its disliked, but that's not why I am asking this question.
Tbh I'm not a great student, if I don't like something I will put...
I have experimental spectrum in which y-axis is intensity values, and x-axis is frequency values. Int - array of experimental intensities (y-axis). w - array of frequencies (x-axis). I know the view of theoretical function that must describe the obtained spectrum. I explicitly set the function...
Greetings
I'm currently designing a lab-script intended for comprehension and use at an undergraduate level. I was extremely frustrated during my undergrad to be dealing with a plethora of uninspired and dull experiments so I decided to take a slightly unconventional (or extremely conventional...
At school I and a handful of other kids are devising an experiment to send up to ISS to test it over a period of 30 days next year. (Yep, we're quite fortunate to have this opportunity!) We've chosen to grow piezoelectric crystals using (super)saturated solution of the piezoelectric crystal...
I’ve been self-studying quantum mechanics for a while, and currently looking at scattering theory, using chapters in books by Shankar, Sakurai, and John R. Taylor’s Scattering Theory text. But was wondering if there are any good sources that relate the theory in these books to actual experiments...
Hello! I am not going to give details about the situation (for obvious reasons) but here it is: I got accepted for PhD to a very good American university, in experimental particle physics and I met a famous professor here who is willing to be my mentor. I talked to some of his old students and...
In the experimental virial equation for real gases,
Pv = A(1+BP) (for small values of P)
as 'P' approaches zero, then why do we get some finite value of 'Pv' instead of approaching to zero value, since 'Pv' is directly proportional to 'P' ?
{P = Pressure of gas, v =...
Hello, I was recently given the task to find experimentally the moment inertia of a sphere. I thought of rolling the sphere down an inclined plane and applying conservation of energy to the sphere. The equations i came up with are: mgh = 1/2mv2 + 1/2Iω2 solving for v^2 we come up with the...
We have been using the equation attached as in image to calculate experiment uncertainty in my class, can somebody explain exactly how this works?
Let’s say we have a value y which is equal to 1/x, where x is some measured quantity with some uncertainty, and let’s say that that value of x is...
Hello!
I have a question that maybe has to do more with Mathematics, but if you do experimental physics you find it quite often.
Let's assume that we want to measure two quantities x and y that we know that they relate to each other linearly. So we have a set of data points xi and yi...
with regards to this https://arxiv.org/abs/1103.5626
"Gamma ray burst delay times probe the geometry of momentum space"
May we have updates of the latest experiment results along the line of Smolin 2011 idea concerning gamma ray burst delay times that can test if momentum space is curved?
Hi All,
my aim is to find the thermal conductivity of litz wire and also convection coefficient of litz wire and air.
So, I am running experimental analysis (10A current into litz wire) and capturing the temperature of litz wire. So, I have temperature profile versus time for litz wire. Would...
I want to design an experiment to demonstrate Raman - Nath effect.
Due to limited resources at my hand (my school doesn't have too much resources), my condition is somewhat like Raman, and hence I want to do the original experiment that Raman and Nath conducted in IISc Bangalore back in the...
Homework Statement
I have a second problem I need assistance with but I'll put it in its own thread.
Used centripetal apparatus to run trials with varying radii but constant mass and calibration weight (mg). I have already plotted T^2 vs r^2 and got a slope of 16.5 from the best fit. I now...
dear physicists
I need all the half life experimental data available so far, for SHNs, I mean Z=104 - 118
(T1/2)
can you help me?
where do I get access to this data?
What is the highest loop order in standard model scattering computations that still contributes a measurable effect seen in past and present particle collider experiments?
In other words, to which order are loop corrections necessary for accounting for observed high energy physics?
I expect it...
Homework Statement
Hi,
I did an experiment where I launched a soccer ball into projectile motion with my hand and took a video the situation. I uploaded it into the Tracker software to analyze it. The tracker software gave me a x-t graph, a y-t graph, and a y-x graph. From the y-t graph...
Hi,
I'm about to finish my degree on Physics (this will be my last year). I have plans to do a PhD with a professor who works too at the LHCb experiment (CP violation), so I'd research on this topics. But I have doubts on the specifical work of an experimental particle physicist... only analyze...
Hello everybody,
I am using an equation of state to calculate the thermodynamical properties of a material. I have a problem which is the ideal part of the equation. Actually, I cannot be sure that the ideal contribution in my equation is the really ideal contribution, so I decided to calculate...
Hello!
I have been using python for my data analysis and processing needs as an experimental physicist for an year now. I have used MATLAB and originpro before and python provides me everything I need.
But I am not satisfacted with my worflow specifically for plotting needs. I often find myself...
What exactly happens during the time gap between the detectors being activated, and the eraser subsequently wiping out the information after the results screen has received the photons? For example, do we "observe" the interference pattern being absent and then (gradually or immediately)...
Hello
I have a bunch of issues with the various interpretations of quantum physics. I'd like to dig into it but most textbooks on the topic just throw in your face a bunch of equations and tell you "that's the way it works"
Intead, I'm looking for a detailed history of the experiments that led...
Based on the paper by Visinelli (https://arxiv.org/abs/1605.06449),
He stated in page 6 that the scalar spectral index as given by the Planck 2013 data (https://arxiv.org/abs/1303.5076) is,
##n_s = 0.9655 \pm 0.0062~~## (##68\%## C.L.)
but when I looked into the Planck 2013 paper, I did not...
Homework Statement
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Q- Hydrated barium nitrate, Ba(NO3)2.4H2O, is strongly heated in a boiling tube and the following changes occur.
Stage 1: The white solid forms a clear colourless solution.
Stage 2: Condensation forms around the mouth of the boiling tube and a white solid starts to form...
I'm an undergrad trying to figure out what career I want to pursue. I consider myself very good at math and physics and enjoy them, however I know that I definitely do not want to go into purely theoretical physics.
I have been thinking about what I want to do for a while now and it occurred...