Device Definition and 531 Threads

Hi, Is solid state device physics a must learn subject to design analog circuits. -Devanand T

Hi everyone, in the last times, I'm really interested in controls engineering, and I wanted toknow how to find transfer functions of devices, or systems in the real world, let me explain better, for example, in my house i have various dc motors, and stepper motors, since i want to make an...

Hi, Is there a device that can attract alpha or beta particles and focus them on a point. Something like the reverse of a CRT tube for electrons. BR, Adam

Homework Statement You are working with a device in a black box which has two terminals, which are in turn, part of a larger circuit. You measure the voltage and the current at the terminals and record the following: vi (V) | i1 (A) 100 | 0 120 | 4 140 | 8 160 | 12 180 | 16 a...

2. A closed, adiabatic device claims to derive useful work by expanding 1 kg of steam from 500 C and 20 bar to 100 C and 1 bar. Do you believe this claim? Assume steam is a real fluid following the steam tables in Appendix A.III.

Favorite Physics "Device" For an upper level undergraduate class I need to give a 50 min. presentation on some physics device. Could you guys give me some ideas for some "cool", but more advanced physics devices, such as a Gauss Cannon (they should be things you could pick up). Thank you!

Homework Statement A spaceborne energy storage device consists of two equal masses connected by a tether and rotating about their center of mass. Additional energy is stored by reeling in the tether; no external forces are applied. Initially the device has kinetic energy E and rotates at...

Hello All, I am thinking about pulsing the power from individual 9-12 volt Batteries @ the different frequencies of 1 Hz, 50 hz, 500hz 5 khz 30 khz and 50khz . All I want to do is to create a pulse DC charge from a 9 volt or 12 volt battery.Car or Motor Cycle batteries are my targets...

Hi, I'm doing a project and i saw a device a few months back that basically, no matter what direction the driving shaft would go the output driven shaft would always go in the one direction. I'm looking for the name of this type of device, or maybe where i can find a site with it It is...

Hi! I am going to be as brief as possible in this question. Im currently trying to design a portable breaker testing device that has a very simple mechanism. Basically, this device must be very small and should be able to fit into something like this:http://goo.gl/BuZ6U When I insert this...

I need help designing a power supply for a portable medical research device for animals. My problem is designing a configuration for multiple voltages with pcb size and power efficiency in mind. I need 3.3 V, +/- 1.5 V, and +/- 20 V. Below I’ve listed device info and estimated current...

Circuits knowledge required for physical electronics? I'm planning to study physical electronics and device/semiconductor physics in grad school. My relevant undergrad physics classes consisted of quantum mechanics, statistical mechanics, electromagnetism, circuits, experimental physics, and...

Hey everyone, I'm graduating with my bachelor degree in physics soon and intend to study physical electronics and device/semiconductor physics in graduate school. I've taken the standard undergrad physics curriculum (quantum mech, stat mech, electromagnetism, circuits, experimental physics) with...

[SOLVED] how to build a device to measure in angstroms Hello, I was looking at a micrometer and wondered how one could build a similar device for meauring in angstroms. Could someone point to some theory that discusses the same ( for example if i have to forge a screw what would be its...

We're talking about high-wattage things like boilers, radiators, etc., things that use something like 500-1500W an hour, but aren't as advanced as computer hardware (where you can tune everything in the BIOS). Can such equipment, even though it's rated for say 800W, consume more (810, 850, 900...

Best digital notetaking and digital education device?? Hi, I'm looking for some digital device that allows me to take notes/make drawings, and adding audio or video to some of the explanations (Just like Khan academy) what would my best options?? I have been looking at the boogie boar, but...

I've heard fuel cells being called energy storage devices. However, unlike batteries, they only convert energy. They don't store anything unless you consider the brief moment of converting chemical energy to electrical energy storage time? Are there fuel cell types that store let's say hydrogen...

Hello, I have been looking for a decent electrical forum for quite some time now. Here is my problem. I own a service and rewind company where we rewind and service electrical motors. We also repair servo motors. A lot of times, due to bearing failure, the magnets on the rotor overheat and...

i am looking to build a device that can communicate with a phone and through that phone you could turn on or off a light or a siren with fairly long range 20 to 30 meters (60 to 90 feet). Would anyone be able to help regarding this device. I am looking for it be as small as possible. also i...

I was wondering if there has been a study done on what happens to a photon wave packet when half out of a device while the device emitting it is moved. If never done it would make an interesting scientific experiment to see where the influence of moving the device ends. I'd like to see...

Homework Statement The metallic sphere on top of a large van de Graaf generator has a radius of 2.0 m. Suppose that the sphere carries a charge of 3x10-5 C. How much energy is stored in this device? Homework Equations So the equation I must use is this: U = 1/2C(ΔV)^2 Q is given; 3 x 10 ^...

So this guy proposed a teleportation device which might one day be feasible, using technology similar to MRI scanners. Since such scanners can create high resolution, 3D models of the human anatomy, Kaku figures that at some point in the future, the resolution would be so high that each pixel in...

Homework Statement The voltage across and current through a device are given by: v(t)= 5cos(4∏t)V i(t) = 0.1cos(4∏t)A determine the instantaneous power p(t) at t=0 and t = 0.25s Homework Equations p=vi The Attempt at a Solution for t=0 I got p=0.5W for t=0.25 I got p =...

I have a grip strengthener which is rated at 7lbs. I'm wondering how that load is distributed among the seven springs. Would each spring offer 7lbs of resistance? If I'm compressing the device all the way, how much force am I really applying?

Homework Statement In an experiment, a small radioactive source must be moved at extremely slow speeds. A positioning device based on thermal expansion was devised where the radioactive source is attached to one end of an aluminum rod and a heating coil is wrapped around a selection of the rod...

This device was in a documentary on Discovery last year. At least that I can recall. Does it have a name?

I was looking through some recent catalogs from electronic stores and a new thing they are trying to hitch is the GPS car tracking devices. There is a major flaw in the system for anonymity, you have to register with a " air time" service to add tracking days and such. For 139 dollars I was...

Hi, I and my team-mate have proposed an idea to develop a CO2 emission reduction device to be installed in automobiles. We have mentioned that it will operate on the principle of 'active adsorption of CO2 on charcoal'. However, although the basic scientific principle is pretty simple...

Hello all, I'm working with an accelerometer to detect movement and I'm using Shimmer IMU. I got values ranging somewhere between 1000 and 2000. My question is, are these values the output of the ADC? And how do i calculate 'g' from the values? I have attached an xls file with the experiment...

What's the best portable device for reading mathematical PDF files? - one that would show equations and graphs clearly? I'm not particularly interested in the general field of electronic books or wireless connectivity, but It would be nice to have portable device for the many free math PDFs...

Anyone have any ideas how I can make one? Please discuss below!:biggrin: The only thing I know so far is that to time travel you have to go faster than the speed of light...

I am designing a pendulum impacting device for an experiment. The pendulum will impact a cart on a track. I'd like to calculate theoretical kinetic energy values for the pendulum at the point of impact. The pendulum is made of a hollow aluminum bar, with a steel plate bolted on at the bottom. I...

I have a fortran program I would like to run on some kind of portable device. Ideally, it would be an older and cheaper device. Does anyone have any advice? The program takes an input from the user (which is an incorrect luminance value read from a 40 year old light meter) and feeds it...

Hi all, I have a number of underwater transducers that I want to measure the impedance of by using an impedance analyzer. I'd like to create an automated system that cycles the leads of the impedance analyzer to the various transducers, perhaps using something like a decoder or a number of...

Hello physics forum crew, I would like some help coming up with one of those "is this possible" type questions. Basically, I'm writing a sci-fi story that is has the strict limitation that all technology must be feasible within the laws of physics as we currently know them. However, there is...

Hello everyone! I am designing a sort of automatic spring gun to use with projectiles the size of normal tennis balls - sort of like a bowling machine. I have a horizontal spring, attached at one end to a square sheet of metal, and fixed at the other end. The square sheet of metal is...

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hi...i want to design a energy detection device fror my home...i want to design it in a way tht it will also automatically switch off unnecessary load when consumption is high above the set value...can anybody help me with the design please...it wud be better if the xplanation is from grass root...

Hi, i wanted to make a laser cutting device, not the big one but a small device just to cut a few mm thick paper. I just learned from a site(www.ehow.com/m/how_6692865_make-homemade-cutting-laser.html) that you can actually convert a laser pointer to a laser cutting device by rotating the...

I need to bias the inputs to a transformer-coupled communications receiver apart by about 100mV. Since the transformer has split windings, one way to do this would be to add a Schottky diode into the center tap, and bias it with a little current (not enough to saturate the transformer). I...

Hi, I'm now in the project research to design a simple low cost and ease installation electric energy detective device. My idea is to put the sensor (etc..) in or within distribution board. Also the device can alarm consumer if they are using more energy. Just want the opinion from you...

If you were to concentrate enough of it in one place, could it generate an antigravity field, similar to the hypothetical 'negative matter'? Only it is proven to exist. I am wondering this because it obviously seems to have some kind of repulsive effect that is exactly the opposite of gravity...

Is there any USB device for simulating... hi Is it posiible to generate analog signal from a USB device. The data to be generated as analog signal is stored in usb or PC to which it is connected ? thanks

Hi Have got a device that is puzzling to say the least. The device is suspended by a thread i.e. no interaction with the ground. I am rotating four tubes each containing magnets which are being rotated into the repelling magnetic field of a magnet that is fixed to the body The following...

I have to make an egg carrying device for and egg drop project. The only restriction is i am not aloud to use a parachute. any good ideas? Thanks, -Cameron

This device was recently purchased at a hardware store, and it has a wattage of 1.1kW but can fit inside a pocket with dimensions of approximately 12cm x 6cm x 3cm. Does it use a neodymium-iron-boron alloy with 44 times the magnetic energy density of iron as the core of a transformer, an...

in physics we have to drop an egg 30ft and the only materials we have is 60cm of half inch thick clear tape, three sheets of paper, and four straws I am thinking about making helicopter blades for it and putting it in a modded paper water bomb with straws and paper bits as cushions but idk if...

I have a audio recorder (Edirol R-09HR High-Resolution WAVE/MP3 Recorder) need to use ac-dc adapter. There is no any marker to tell me polarity of input in this device. (I check the adapter from amazon.com for this device which I do not have, there is no marker as well) I have a Radio-Shack...

Homework Statement An insulated piston-cylinder device contains 5 kg of water at 100oC with a quarter of the mass is vapor. The water is compressed reversibly to 900 kPa. Find the work done during this process. Let the ambient temperature to be 27oC. Homework Equations I can use the...

Visible light, like sunlight, consists of photons. Each photon has a level of energy (radiant energy) directly proportional to its frequency. Does anyone have any suggestions on any device to measure the frequency of Photon? Thanks in advance for any suggestions