What is Experiment: Definition and 1000 Discussions
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.
Homework Statement
a) Imagine that you are conducting an activity with a laser to create an interference pattern. Use the appropriate equations to predict two ways (other than the way described in the following example) to change the interference pattern in order to have closer fringes. Explain...
Dear Sirs,
I have a question regarding the interpretation of the Michelson-Morley experiment.
As I understand it, the special relativity theory implies that, say, if I were to watch another person in a n inertial reference frame (say a vehicle) moving relative to me send a light beam towards...
If I wanted to design an experiment which would allow to distinguish muons from pions in the energy range from 200 MeV to 2 GeV, how would I do it in a simple way? Could I just use the Time of Flight experiment? What quantitative arguments can one make for the design of the detectors?
1. So, during one of my classes, the teacher showed us a small experiment, and asked us to explain how it works. The experimented consisted of a tube, closed on both ends, and attached to said tube is what I think is a magnet. Now, everytime he rotated the tube, the magnet rised to the top with...
I have performed an experiment testing how mechanical energy is conserved. I conducted this experiment by first creating a ramp. I gathered data by first calculating the gravitational potential energy of a marble on various points on the ramp (depending on height). Next I rolled the ball down...
Hello everyone,
I was re-studying some issues that I wanted to repeat in magnetism and the moment I saw the stern gerlach experiment again, I came up with a question: what would happen if we kept this experiment exactly the same, but this time we used electric field only, instead of magnetic...
A few question about the double slit experiment... I have watched many videos and discussions about this experiment and am curious if anyone has ever varied the slits... What happens if one slit is vertical and one horizontal? If they are closer together or further apart? One fat and one...
Hi, a fast question while I was reading the results of the Wu experiment:
http://iktp.tu-dresden.de/uploads/media/Experimental_test_of_parity_in_beta_decay_-_Wu.pdf
It says that "the observed gamma-ray anisotropy was used as a measure of polarization and effectively temperature"
However, I don't...
Homework Statement
In the Cavendish experiment, the two small balls have mass m each and are connected by a light rigid rod with length L. The two large balls have mass M each and are separated by the same distance L. The torsion constant of the torsion wire is κ.
b) Put the large balls a small...
Hello! I've been reading up about Quantum Mechanics, and I'm trying to understand various aspects of the double slit experiment.
This is one of among many videos I've watched: Dr Quantum - Double Slit Experiment
Here's my understanding so far of the basic setup (where the gun is shooting out...
For my undergraduate physics lab, we are asked to spend 3 weeks (3 3-hour sessions + any time during the week if I need extra time) doing an experiment of our own choosing. The physics department will provide any experimental tools needed within reason.
I have been considering using this...
Homework Statement
A high school experiment shows a plant immersed in a solution of nitrate ions. The beaker is closed but has an air vent passing into the solution.
Q. Why is air bubbled into the solution
Q. Why is the beaker covered with black paper
Homework EquationsThe Attempt at a...
Homework Statement
In a KhanAcademy video, light of wavelength 700nm shines through a double-slit whose holes are spaced 1300nm
apart. If a screen is placed 3m away from the double-slit, what will be the distance from the central bright spot on the screen to the next bright spot...
Homework Statement
The diagram above shows a single slit with lines marking the direction to a point P in the diffraction pattern. Two wavelets at x and y pass through the edges of the slit as shown. The possible value for path difference, py-px, that places P at the second nodal line next to...
Homework Statement
Investigating the effect of mass on the period of oscillation.
This experiment is about SHM of a floating cylinder, and the theory is explained in this website:
http://physics.stackexchange.com/questions/64154/shm-of-floating-objects
Also, I'm attaching a diagram of my...
I've gone ahead and uploaded the paper I had filled out during class.
For this experiment, students must be able to find the acceleration of a cart using kinematics, dynamics, and energy. A cart with a mass on it (mc=2.48kg) is connected to a mass-less string which is connected to a pulley...
"An interaction is required to manifest physical reality because it creates distinctions."
my friend referring to the double-slit experiment, is it true?
He said that the physical world, in order to exist, we need to interact (with our senses) lol
Hi, I want to varify something that I intuitively know (I think), that might not seem intuitive.
If an electrical current is circulating and then it's path splits in two, where there is a circulating current. The larger current (black) will have to pass through this loop; what I want to varify...
According to JJ Thomson's atomic model, Rutherford expected deflections of alpha particles through small angles. I'm unable to understand why he had expected "small angles". Can someone please explain.
Hi!
I would like to create an electric field inside a cylinder. Is there any EXPERIMENTAL way to impose 120V DC (or any higher or lower) voltage on the surface of a cylinder and generate electric field inside it?
I'm specifically looking for "experimental" approaches.
Thank you very much :)
Homework Statement
Let's say I have a Langmuir probe I-V characteristic from the Helimak experiment. The plasma ions are singly ionized argon. The probe has an effective area of 0.000016 m^2. Estimate the floating potential, electron density,
and temperature. Based only on the nature of the...
Hi,
I read the quite common introduction to the Bragg's Law, but there are some points I have not clear at all; I hope you can help me.
1) The book says that, for the diffraction to be evident, the wave length of the incident wave must be comparable with the order of magnitude of the...
Homework Statement
A quasi-monochromatic beam of light illuminates Young's double-slit setup, generating a fringe pattern having 5.6-mm separation between consecutive dark bands. The distance between the place containing the apertures and the plane of observation is 7 m, and the two slits are...
Hi all,
just I made my own Chladni Plate or CymaScope and have played a little bit with it:
I was curious and I made some tests with guitar:
but my question is: does enyone know why this is happening?
Hey everyone, I was just wondering how the detectors on the slits operate. The ones which supposedly observe the particle without altering it's trajectory too greatly. I have no idea how this would work with a photon. I'm assuming it's easier with an electron or something.
Homework Statement
How close does the alpha particle gets to the nucleus in gold foil scatering experiment?Homework Equations
Ek = 2.0 MeV
W=F delta x
F=(kq1q2)/r^2
W=(kq1q2)/r
E=W=(kq1q2)/r
The Attempt at a Solution
E= (k(79)(2) e^2)/r
2.0MeV= (k(158)e^2)/r
2,000,000 eV = 8.99 Wm^2 c^-2 ((158)...
I'm know I'm just an enthusiastic newbie here, but something's been nagging me and I would appreciate if I could get some assistance on the matter.
I got a notion about light and the double slit experiment, the notion came to me as I was contemplating light traveling at its native speed. For...
A coin can stay upright on its rim for a some time when rolled with a some velocity, while it falls from its upright position at the slightest disturbance when stationary. I did not understand why it happened. I just dropped a few coins on the floor and noticed this thing which is very new to me.
Can @Drakkith , @Doc Al and others help me in this?
In YDSE,
if s is the size of source slit and S is the distance between source slit and the double slits,
Then why condition s/S <= λ/d must be satisfied to observe fringes?
Here λ is wavelength of light source and d is the distance between two...
What is the effect on the interference fringes in Young's Double slit experiment when the source slit is moved closer to the double slit plane?
I have seen you people @DrChinese , @Cthugha , @bhobba helping in these kind of topic before.
Can you help here?
It would be great if others also can help.
Homework Statement
An accelerator experiment collides a beam of electrons head-on with a beam of positrons. The particles in each beam have energy Ee as measured in the lab frame. Suppose one electron-positron pair collide to form a photon and neutral pion particle:
e- = e+ ---> γ + π0...
If we increase the mass of the particle beeing fired at the slots, at what point will the standard experiment break down and become just small pellets beeing fired and classical physics will apply?
Theoretically say we increase one Planck unit at A time.
Or, just is there A limit to the...
The scenario involves dropping something into a bucket of water. I'm trying to do an experiment where I have to figure out a relationship between the amount of water that leaves the bucket and a certain variable of the object that is dropped.
I'm wondering what could maximize the water that...
In the charged rod experiment, why didn't my hand neutralize the charge formed in the rod, since my body is a conductor and it is connected to the Earth?
First of all, I want to apologize ahead for three things:
1) Opening another tread about this experiment, with probably the same title than other 800 threads: I took a little time to read the other threads with similar titles and didn’t found this doubt in none of them, and also didn’t seem...
1. Homework Statement
A student was investigating the reaction between sodium thiosulfate solution and dilute hydrochloric acid. As the reaction takes place a precipitate of sulfur forms in the solution and makes the solution change from colourless (and clear) to pale yellow (and opaque). The...
Homework Statement
Hey guys, so I'm doing the an exercise on the Kater's pendulum, to calculate g. I've gotten down my g calculation to g = 9.80658m +/- 0.00054 using equation 1 below. The errors taken into account are just on the kater period T and the distance between the two pivot points (L)...
Hello!
I have questions in regards to the Two Slit Experiment. If the photon splits in two and passes through both slits at the same time and interferes with itself on the other side of the screen and then it hits on the second screen thereby creating the interference pattern. At what point...
Homework Statement
For my coursework task, i am to quantify and discuss errors associated with an experimental procedure.
This involved a thyristor control unit which allowed the firing angle of two thyristors (in a half controlled bridge rectifier) to be varied with a rotary dial or pot/rheo...
Hello,
Theoretically any object can convert into black hole by compressing its mass below some radius( describe by Schwarzschild Radius). Suppose one of this object after becoming black hole have radius
which is comparable to atoms and nucleus radius. Now my question is what will happen if we...
Hi!
I'm new here, so I apologize on beforehand for any mistakes I may make (grammar/wrong thread etc.).
Currently we are doing a project for our exam in my class, and in my group we chose to focus on the following scenario:
On a spinning "plate" (you know, like a merry-go-around... sorry, I'm...
In Davisson-Germer experiment the necessity of constructive interference is dsin(theta)=n(wavelenght) but in Braggs law its 2dsin(theta)=n(wavelenght), why are these two different? I saw that Braggs law is used between layers of crystals but I've also seen Davisson-Germer experiment's equation...
like a person with a background and just the background really fast, like a strobe effect. If you cycle back and forth fast enough would the person appear like normal or 50% see through?
Homework Statement
In 1911, Ernest Rutherford discovered the nucleus of the atom by observing the scattering of helium nuclei from gold nuclei. If a helium nucleus with a mass of 6.68 10^-27 kg, a charge of +2e, and an initial velocity of 1.30 10^7 m/s is projected head-on toward a gold...
Lets suppose device A measures the position of a particle very accurately. Device B now cannot measure its momentum to high accuracy due to the uncertainty principle.
But let's suppose that neither A nor B can ever communicate their findings to the rest of the world. Now the uncertainty...
A question...
Perhaps a dumb question...
A simple question... or maybe not...
In the experiment, why are the slits needed in the first place?
If one shoots electrons, then the edges of the slit must therefore do something with them in order to make them act the way the do: the seem to...