Drive Definition and 496 Threads

My portable hard drive has died on me, is there any software (preferably free) that can help recover the contents?

Homework Statement 1. I have been recently wondering how is data stored on and retrieved from optical devices like CDs, DVDs, and Bluray. What makes these different storage types different from each other? 2. Why will a silver mirror not show a reflection when you sand the surface with...

I have been recently wondering how is data stored on and retrieved from optical devices like CDs, DVDs, and Bluray. What makes these different storage types different from each other? Why will a silver mirror not show a reflection when you sand the surface with very coarse sandpaper? Is it...

Hi everyone, I have been reading the fascinating paper by Miguel Alcubierre about the warp drive and one thing is confusing me. He says that the total co-ordinate time is T= \left[d/v + \sqrt{(D-2d)/a}\right] Would that mean that the warp bubble is constantly accelerating so its...

I'm sure a lot of you have heard of the warp drive theory. I can't seem to find much on the bubble part, though. In theory, will the bubble be something you can actually see and touch?

Homework Statement The hard drives of many desktop computers spin at a maximum rate of 7200 rpm. If the diameter of the spinning disk in the harddrive is 3.51 cm, calculate the magnitude of the centripetal acceleration on the outside radius of the disk. Homework Equations ac=v2/r...

I think I have a rough idea how to get there...but I'm not sure. Let's assume I'm riding a bicycle, and I'm peddling at a constant pressure (torque). This is a peddling pressure which would be the exact amount which would just lift a 50 pound weight off the ground and hold it there...

Hi everyone, i'm new here. i want to know how to clone the hard drive of computer. which software is the best? i heard about norton ghost but is an alternatives? And is it possible to find a step by step procedure to do this. Than you very much 042012

Its not an actual homework question just principals I am unclear on. Its in relation to a standard bicycle being driven by a rider How would I calculate the minimum torque on the back wheel? How would I calculate the maximum torque on the back wheel? How would I calculate toque on the...

Was cosmic inflation partly driven by the quantum degeneracy pressure of the quarks and electrons? Just after the Big Bang they would all be sitting on top of each other - just what fermions don't like to do!

I have uploaded the journals which related to the brushless dc motor. I encountered the problems as i don't know how to simulate the voltage source inverter of the Brushless dc motor system (the generation of inverter line to line voltages) and the hysteresis current block. i really need help...

Actually i am using lead screw drive by motor along with rope drive. If you will see the attachment, yuo can clearly understand the working principle. In this working priniciple, when we used to start the motor, carriage power use to go up through lead screw drive.Rope is connected to this...

firstly it is supposed to travel at the speed of light and not FTL right? That is the limit to gravitational waves as well right? And what are present problems on it?

In order to operate, nixie tubes need 170 VDC. I know that the mains voltage is 120 VAC-RMS. So if you account for the RMS value, 120*1.414 is nearly exactly 170 V. So would it be possible to make a full wave rectifier? I decided to simulate the circuit in spice. If I use a 500 uF capacitor...

My laptop is equipped with hard drive shock protection. If I am watching a movie and the accelerometer senses a perturbation (me shaking the computer) the image is immediately frozen, but there is no interruption in the sound. Why is this the case?

I've currently using a signal generator into the gate of a MOSFET to switch an inductive load. I've built a 555 circuit to replicate the signal generator output (TTL 5V 192kHz). When I connect this to the gate, the power supply driving the MOSFET limits the current and shuts itself down...

Hi all, I have a question with regards to why should we use an ac-dc, dc -dc, dc-ac converter to an ac drive? Why not connect an ac source through a transformer directly to the ac drive? Isn't it the same? What equations can prove that the use of converter is a better choice?

This is not a perpetual motion machine; the fusion power plant will run out of nuclear power to provide electricity to power it; and this type of transit drive works in theory by having two combustion chambers positioned parallel to the spacecraft 's width and perpendicular to its length. Each...

When you drive a .36 kg apple, Earth exerts a force on It that accelerates it at 9.8 m/s squared toward the Earth's surface. According to Newtons third law the Apple must exert an equal but opposite force on earth. If the mass of the Earth is 5.89x10^24 kg,what is the magnitude of the Earth's...

thanks to read my message after transfer my document and plug out my external hard " my passport 3.0 500 g.b " all data delete , please help me

Suppose we have either a massive or massless complex field in 3 space and one time dimensions. Suppose we force (or drive) the field on the surface of a small sphere with a function like, exp(-t^2)*exp(-iωt) I'm guessing the result of such forcing will be a circularly polarized wave that...

http://homepages.enterprise.net/jayjay/cdrom_motors.htm So this is modified brushless motor. It says that it uses jeti06 ESC. But frankly I am not ready to sneeze 25€ for a ESC. How do you drive this in principle? You send pulses into those 3 windings, one after another...

"Phantom Drive" "H" I believe I may have removed a thumb drive or maybe a USB hard disk drive without unmounting it. I have a drive "H" that I can't get rid of. I am running Win 7, intel quad core. Is there any way to "remove" the drive? Paul

I have a laptop and I'm running Windows 7. I recently downloaded AutoCAD and some other CAD software and I needed extra storage space on my laptop, so I bought an external hard drive. I was wondering if there was any way I could reinstall any programs onto the external HD to clear up some...

Hello! I have accomplished creating the USB boot able flash drive, That boots with DOS, I had thought this would be the perfect way to take control over the hard disk when my Operating system is corrupted.. But it's not. On the Dos windows drive c: is shown but I don't think that's my hard disk...

Homework Statement A solid drive shaft is connected to an engine by a coupling, which has drive pins located on a pitch circle diameter of 80 mm (Note: the diameter of the pitch circle is greater than the diameter of the drive shaft). If the maximum power output of the engine is 90kW at 5000...

Hi, I'm currently trying to work through a problem about calculating the most likely time for a hard disk to fail: Hard disks fail with a probability per unit time: \alpha (t) = \alpha _0 t where \alpha_0 = 0.5 years. I know that the answer is t_{modal} = \frac{1}{\sqrt{\alpha_0}}, but am...

Okay... SO... According to the implications of Alcubierre's peer-reviewed, published theory... According to his equations, would the Alcubierre drive produce any gravitational waves that would spread outwards from the source? From what I understand, there's considerable manipulation of space...

in many research of kaluza klein theory to unified electromagnetic & gravity fields these research begin with 5D metric how can i drive this metric? please any research drive this metric show me. note russian research's by english is very good if you know it show me . please it is very important

Hi, I was wondering if anone knew what an internal CD or DVD drive case is most commonly made of. I was hoping to use it to do some welding so am hoping it is steet but not sure. Cheers

Hi I will get straight on to the problem. I want my RC servo motor to run when there is no light from 0-180 degrees and when there is light the motor should stop. I have made a program which reads the voltage from sensor and a program to generate PWM signal witha a timer sepraretly as a...

1. Ok I have to build a real life wave-maker for my Final Year Project(FYP). My wave-maker design is as shown below: http://img696.imageshack.us/img696/5888/drawntank.png The proffessor said I need to be able to calculate the torque of the motor before I order it. I start out by calculating...

Hi there, does anyone knows the overall dimension for 2.5' hard disk drive?including all the components inside. who has the complete dimension? tq =)

Hello. What do you think about Warp drive? And what do you think about it, if the warp bubble is created with a magnetic field? Thank you.

I am a hobbyist, and I am not too familiar on to how to run motors. Can someone help me design a simple circuit that drives a dc motor on pulley drive of a conveyor belt. The conveyor belt has to stay on for 5 seconds after a switch is turned on. The belt is about 48 inches long, the radius of...

Hi all! I am not asking anyone to tell me how to install this hardware, I just cannot find anywhere on the internet that will give me instructions on how to install this internal drive! I have a Sony VAIO VGN-NW240F and the existing drive is inoperable so i purchased a new internal drive to...

Ookay, previous thread was locked out without receiving any help - to the mod in question, I'm asking for assistance in analysing a result, not trying to argue (much less prove) any particular conclusion. I uploaded videos to YT so that anyone wishing to assist can see what the problem is. How...

Brief description of problem: two independently-suspended platforms of equal mass are subjected to an intervening EM impulse, driving them apart. Upon the platforms are set a pair of solenoids to provide the impulse, and additionally a pair of pivoting magnetic armatures on one platform only...

Homework Statement A computer disk drive is turned on starting from rest and has constant angular acceleration. If it took 0.690s for the drive to make its second complete revolution, how long did it take to make the first complete revolution? What is the angular acceleration?Homework Equations...

Hey, long time no see! :-D Well the subject line pretty much says it all. When I plug in my Simple Save external HD it does turn on, and my computer does recognize it. But when I try to open it I get an error message "F:\ is not accessible. Access is denied." Also, when I plug it in Windows...

If an electric current is passed through a conducting magnet at a right angle to the magnetic field lines, the magnet should experience a force at right angles to both the flux and the current. This is a linear version of the homopolar motor. Since the magnetic field is not attached to the...

I am a 23 year old male virgin who is unattractive and unable to secure a relationship with a woman he finds attractive. I have tried being with women who are equally attractive as me and doesn't work I just am not attracted to them. My issue lies in the sex-drive I am ok with being a virgin but...

Hi, so I'm trying to troubleshoot my gf's external hard drive and I'm looking for some advice or suggestions on things to try. Basic specs: Age: 1 -2 years Capacity: 500gb Interface: USB 2.0 Brand: Western Digital She was just transferring files to it and suddenly it became super...

Firstly, I am not an engineer or engineering student. I come from an art/creative background. However, in what may be arrogance, I'm convinced I can solve a problem that no one but me thinks is a problem. Further, I'm spitting in the face of a system that has been fine for everyone else for...

First of all this is not a perpetual motion machine and is not the previous U Reusable Fuel Transit Drive I designed earlier. This type of transit drive, which doesn't reuse fuel, works in theory by having two combustion chambers and their respective exhaust nozzles positioned parallel to the...

Hi, this problem’s been bugging me for ages. I’m sure it’s just a simple misunderstanding somewhere on my behalf but I just can’t seem to get my head round it. Homework Statement A monorail car with front wheel drive and mass of 5 tonnes is suspended from two wheels 10m apart as shown. Its...

I am using 4 MOSFETs in an H-bridge. The H-bridge is controlled with two MOSFET drivers (specially IR2113). I aim to drive the H-bridge via PWM which is carrying a 50Hz sine wave. Note that, the load is not a motor. Instead, the H-bridge is being used as a inverter. My question is, does the...

Does anyone have any experience with replacing a laptops hard drive with a solid state drive? I want to buy a cheap little laptop, an Acer, but also buy a solid state drive and immediately swap out the mechanical drive for a solid state drive. Does anyone know if this is typically possible...

I have a unique problem in that I would like to test out an operating system on a PC (M1400 Tablet) that has no Hard disk. Before I had the tablet I had assumed I would be able to boot it up using a thumb drive to test out the Linux support for the stylus. Anyway, the Bios doesn't expressly...

One of the all-time great science mysteries is now a step closer to explanation. The surface of the sun, known as the photosphere, can reach temperatures of 5,000 degrees. To many it would seem logical that the temperature would lower further away from the sun. But, the outer atmosphere, known...