Detector Definition and 263 Threads

Hi guys, I am new at this so sorry if i get the format wrong. Im trying to build a basic metal detector that will respond when a steel pendulum passes nearby. A simple response is all that is needed right now. I thought of this: Building a RL circuit with a copper coil air core. placing a...

Homework Statement A pair of bare copper wires a, b is attached to a basement wall to detect the presence of moisture. Design a circuit, using a darlington transistor, to turn on an LED if the current flowing between the wires due to the moisture exceeds 10μA (use a current-sensing resistor...

Hi guys, I am working on a Automation project and I am wondering whether there is any probe that can emit signal to a standard PLC when iron rod is found inside a concrete wall. Personally, I hope it can be avaliable from RS. Thanks for your kind help in advence.

Dear all, here's my first request for a little help (maybe also in finding the proper subforum...) I'm working as developer and scientific consultant in a lab for Nuclear Magnetic Resonance at high field (> 21 Tesla), and I have to create a suitable probe for checking the stability of a...

How does a screen make a particle behave differently than a "detector"? I was reading a 2007 Newsweek article Putting Time in a (Leaky) Bottle. In one version of the double slit experiment, if you fire photons through double slits and have a screen on the other side, your results are a wave...

I am first year EE student so forgive me if there is huge lack of knowledge. While reading ahead in my physics book I found out that metal detectors in airports, courts etc are basically transmitters and receivers. If metal gets in between the detector sets off the alarm. What if then, there...

Homework Statement A super nova releases 1.9E45 J of energy over a 10 day period. It is 1560 ly from earth. A detector, facing the star, is a disk of radius 7cm. How much energy reaches the detector? (The detector is in orbit, so it can face the star for the entire 10-day period) Homework...

Hi all, Got a bit of a problem with a lab experiment at uni (I'm not sure if this is the right place to post this, mods feel free to move it if necessary!) Anyway: We're trying to get a plot of efficiency against energy for a planar germanium detector. We've got spectra for different...

Hey guys, I'm a first timer here, and need just easy pieces of advice. I'm pretty into cars and have a decent electrical knowledge behind my mechanical know how, just not with reading schematics. Recently, my 12V socket died and I finally have an excuse to hardwire my Escort Passport...

Homework Statement How Can you use triode as detector in radio wave receivers?Homework Equations N/AThe Attempt at a Solution when the radio receivers were invented , triode was used to detect them but what function enables this is our of my mind!

I need a list(data numbers) of short range IR emitter and detector(not very expensive) which can be used as a break beam sensor.. I also like to know what is the specific IC number which is used to tune the IR emitter's frequency which matches with the detectors receiving frequency. I have heard...

Nooooo! The battery in the one in my bedroom must be getting low because it has started making a very loud chirp ever couple of minutes and there is no smoke. OMG, if this continues, how do I take it apart? I see a button in the middle of it, will that kill it?

Homework Statement I have always been told to remove anything metal before walking through a metal detector. Why is it bad to take a laptop through a metal dector? How can I give me answer in the language of physics? I cannot just say that it will probably scramble my internal memory and...

I want to use an "inductive proximity sensor" for metal detector gate, but the problem is its range is (generally) under 50mm (2 inches), is there any way I can increase its range? or is there any alternate sensor or way to detect the metal ? Thank you. Faraz Nizamani

Hello to you all, I have seen something at a friends work place and did not understand how it worked? after asking I didn’t get an answer that satisfied me. The company produce voltage detectors and test them on a single phase 50kV transformer. One output post is connected to Earth and the...

I need a telephone to answer when called, dial a number on another telephone, and then hang up when the caller hangs up. I have both the pick up issue and the dial issue solved. The mail problem is the hanging up after the caller hangs up. I'd be very happy if I did not have to use a...

I recently did an experiment to measure the activity of a radioactive source, with the idea that the activity can be found by treating the detector area as part of the surface area of a sphere. In the actual experiment, we plotted u = \frac{n d^2}{\Delta t} against d, where d is the...

Hi! I am looking for a sensor that can sense radioactive particle. It will alert when the amount of the radioactive particle in air is high. I found many radioactive detector, but I need is the sensor in the detector. Can someone suggests for me this kind of sensor (as small as possible)...

I am looking for an electromagnetic field detector that can detect use to detect the intensity of wave on a grid and return the results to a computer. the higher the resolution the better. does anyone know where this can be purchased? how could one be designed?

Basically I am wondering if the act of detecting the path which the electron didn't go affects the interference pattern. But I'll be more specific. So we have the double slit experiment with electrons, they have a 50/50 chance of going through each slit, and if we have this setup we will...

Im not sure if this should go here, but. . . Im building a motion detector. I have the breadboard hooked up the following way using an op amp, a potentiometer, photocells, resistor and led. http://img6.imageshack.us/i/breadboard.jpg/ So it seems to work fine, but I wanted to...

I have a question about the situation with the two slit experiment where detectors are placed by the two slits to determine which slit the particle has gone through (and destroy the diffraction pattern). Okay, so what I'm wondering is what happens if the detectors' accuracy is not fixed, but...

Homework Statement I'm not sure if this is really introductory physics... tell me if you think I'd have more luck in the advanced physics section. The problem: You have a gas filled counter, in the form of a parallel plate capacitor. It has capacitance 9.1 x 10-9 F. It takes 20 eV of energy...

http://cmsdoc.cern.ch/cms/performance/FirstBeam/pictures221109/CollisionEvent.png Garrett Lisi has mirrored the official site, in case of any problems with accessibility. http://sifter.org/~aglisi/albums/LHCfirstcollisions.png

My first thread here. Please bear with my lack of knowledge. I talked to a physics grad student about whether it's fair to describe QM as a theory applied only to microscopic objects. Although the definition of "fair" is ambiguous, at least he told me that, from his understanding, he wouldn't...

This is not homework, although I am an EE student. If the solution is cool/complex enough, this might become a design project, although it'll most likely end up as something to do over the summer. some time ago, I purchased a motorized doggie door. The dog wore a high frequency sound...

Hi.I wonder is it possible to create a home made muon or gamma ray detector? And if it is possible would you mind to show me some way? Thanks...

Homework Statement A detector is made up of 64 by 64 detection strips - perpendicular, i.e. 64 strips along the x-axis and 64 along the y-axis. Particles impact along the z-axis, evenly distributed among the detector surface. When a particle hits the detector, one x-strip and one y-strip...

Homework Statement I am building an audio equalizer as a project for class, consisting of a summing amplifier with variable gain for the bass, midrange, and treble frequencies. I also have the option to include a clipping/overload detector, though I have already chosen parameters that will not...

My group had a design based on the http://www.analog.com/en/rfif-components/log-ampsdetectors/ad8302/products/product.html" which was going to do our task of phase detection by use of what I can best tell was just some log amplifiers and . Well the AD8302 is a TSSOP package and I cannot...

I am playing with some accelerometer data and need to filter out the noisy output. How do I implement a Low pass filter in excel? I tried avg, rolling avg. They all smooth out the data but not what I want (averaged accn is finite when it is actually zero!) If I can create an envelope...

Homework Statement A microwave detector is located 0.5m above the surface of a large lake far from the shore. As a star, emitting monochromatic microwave radiation of 21cm wavelength, rises slowly above the horizon, the detector indicates successive maxima and minima in the signal...

Assume that the density of dark matter near the Earth is 0.3 GeV / cm3 and that the dark matter particle has a mass of 100 GeV and a velocity of 200 km/s. If the dark matter-nucleon cross section is 10-44cm2 calculate how many events you would expect to see every year in a metre cubed volume of...

I am looking for someone that can tell me how to reproduce this experiment sen on nova last week A rectangular black box was used with a low power ? 1mw red laser . A long box was used there were 2 vertical openings left and right of the laser path to the photon detector. There was no direct...

Can anyone suggest me the link where i can find power-point representation of various detectors (including scintillation detector).I had found the theory regarding these,but was unable to detect some flash or animation or some power point representation.

Photons Detector not yielding "which-path" info. In Fabric Of The Cosmos, I am just getting through the part where Greene discusses a multi-path setup (7.5?) involving a series of beam splitters and downconverters, whereby photons striking two of four detectors will yield definitive...

Not sure whether or not this should go here, but this seemed like the most accurate place since my question is about how an instrument works. I have an old unused Waters 440 Absorbance Detector for HPLC that I've scavenged for parts to try to digitize an old polarimeter. What I'm trying to...

What is the typical efficiency (as a function of muon energy and/or rapidity) of a moun detector at an accelerator experiment? More specifically I would like to know about the lower energy treshold: E.g. if a muon with energy of just some few GeV is produced in the collision process, what is...

There has been a spate of writing in the popular media about the debates between scientific teams regarding various WIMP (Weakly Interacting Massive Particle) detection devices in the search for Dark Matter. (Example: http://www.nytimes.com/2008/04/17/science/space/17dark.html?ref=space from...

Homework Statement A detector hjaving a radius 10 cm is placed 1 m away from an electric dipole. What fraction of total solid angle does the detector cover and what fraction of total dipole power does it detect (assuming 100% detection efficiency) 2. The attempt at a solution I drew the...

Hi nerdy geeky folks, I have two questions: 1. can a regular cadmium-sulfide detect infrared in a complete absence of light (but a beam of infrared)? if not, what can be used to detect infrared (for a beam break sensor)? 2. I just want to make sure that I am building the circuit right...

I recently bought a phototransistor emitter and detector from radio shack: http://www.radioshack.com/sm-matched-infrared-emitter-and-phototransistor-detector--pi-2049723.html . It didn't come with much instruction but i thought i could simply put a voltage across the emitter and the detector...

In a response by Pervect to another topic, he mentioned a device called a Forward mass detector, named after its inventor Dr. Robert Forward. It's an intersting device with the claim that it can detect small gradients in the curvature of spacetime. I couldn't find any info regarding...

I thought you guys might find this interesting click http://www.nytimes.com/2007/04/03/science/space/03stat.html?_r=2&ref=science&oref=slogin&oref=slogin"This seems criminal to me.

<sarcasm>Since lie detector tests are very very accurate (like 99%), we should use them as an alternative for human grading. So what do you think? I believe it would obviously work due to the use of the lie detector test in law enforcement. It can save the teacher a lot of time because since...

Can i get some help with this problem? This problem deals with the basic loop configuration you will use in the laboratory to construct a metal detector. Two concentric circular coils of wire lie in a plane. The larger coil has 49 turns and a radius of a = 7.90 cm. The smaller coil also has 49...

hello, I have to make a sensitivity model for a near infra red detector and I need help. I have so far done radiometric calculations taking into account noise, due to dark current, sky background, etc and calculated the minimum signal intensity i need. However, i have a few blocks: I need to...

hi! a ball is dropped from a height of 1 meter above the floor. Take the origin to be the point from which the ball is released. would the graph be like a curved graph rising to the right starting from the origin? how would the graph look like if a car is parked on a steep hill? thank you

In industry, do you use gamma ray or beta ray to detect oil leakage?

Please guys I really need your help. How does a photo detector detect? Can you also tell me where you got the info from. thanks einstein2603