Practical Definition and 323 Threads

Consider a DC motor, being switched by a H bridge that is controlled by a PI current regulator. As long as the error (SetCurrent-Current) is positive everything is good. However, when this goes negative we have a problem as you couldn't set a negative duty cycle. How is this solved in...

Hi, I'm currently a second year mechanical engineering student. As part of my course, there is an opportunity to go on a year long placement to an engineering company next year. I have to start applying to companies now, so began to brush up my CV. The problem is, I have next to no practical...

I'm majoring in mechanical engineering and I have a lot of open room in my course schedule the next few years. What are the most useful electives I could take? What courses are the most useful in industry? What have been the most useful courses you've taken for your career? I'm interested in...

Hi, I did read an article (Norwegian one) about heat pumps. Several owners claims that the annual costs for operating a heat pump versus a traditional electric stove isn't much different. Even if the heat pump isn't reversed at hot days in the summer (And used solely for heating), these...

Homework Statement Practical on determining if a burette is more accurate than a measuring cylinder Method: The burette was filled to a mark above 45cm3 with water and the reading recorded. The burette was opened and 30 drops of water were allowed to be delivered into the measuring cylinder...

Hello Everyone, First I would like to thank you for allowing me to post in this community and Would like to Give a brief background about me: BEng (Hons) Degree: Aerospace Engineering from UK MSc Degree: Advanced methods of Aeronautical Engineering from UK Basically a Fresh Graduate...

Can anyone say how close we are to obtaining a workable nuclear fusion generating plant? I understand the largest trial is being built in France (albeit with many delays apparently) Does anyone have any understanding as to what the best guess is to this technology being available to the...

Evo don't you dare close this thread I want at least one answer as to why it can or can't work :P So sinse we can strap electrodes to our heads and with nothing but thought, we can make something happen, whether it's moving a rats tail, moving a ball bearing or making someone elses finger...

I want to pursue my Masters in Research in the field of Quantum physics. I would like to understand the practical usage of quantum physics for eg: where it is used in real world and if any books to refer regarding the practical usage. I have good collection of books on quantum physics which...

If an inert gas is used to force piston with a Pressure say P (Assume the volume of gas to be sufficiently large). I would like to know the following: (consider piston to be horizontal) 1) If say one puts a small volume of a hydraulic fluid in front of the piston. Keeping the same pressure of...

I just Read arithemetic for the practical man and found really interesting...there's also Algebra for the Practical Man,Geometry for the Practical Man,Trigonometry for the Practical Man,Calculus for the Practical Man And everybody knows that the great feynman learned from these books...I would...

Is it a good first calculus book? Feynman used and liked it. it especially made for self study and that's what I need...did any of you use it? Is there something better?

Hello everyone, I was wondering what is the most practical/hands on engineering specialization in mechanical that would not require someone to stay in front of a computer 8h a day, 40h a week because that is what I've mostly been doing at my internships so far (CFD simulations, excel, tecplot)...

Homework Statement In the practical for calculating speed of sound using the resonance tube why do we put wool to the bottom of the cylinder? Homework Equations - The Attempt at a Solution To prevent the tube from hitting the bottom hard for it can be broken.

Hello, I need some examples of practical second order differential equation that can be solved by Runge kutta method. I tried searching on net but couldn't find a satisfying answer. Please help.. Thanks in advance

Homework Statement Hi guys, The title says it all pretty much. I need to know a handful of practical uses for each of the following, in the context of oscillatory motion (springs, pendulums etc): 1) light damping 2) critical damping 3) heavy damping Homework Equations Light...

Hey guys, I have a few questions I would like to ask if that is okay First off: I was doing an experiment regarding Boyle's Law, and there are some questions that accompany it. I had a syringe filled with gas and I had to add mass on the syringe so that the piston moved down. I had to convert...

hello all, i am a second year computer systems engineering student, after my first year i have done well in the theory. but i find i learn so much more when a unit has practical backing. i have decided to build an electronics lab so that i may practice various topics in engineering that i learn...

Applications: garage door openers: 40.0 , standard cordless phones: 40.0 to 50.0 , baby monitors: 49.0 , FM radio stations: 88.0 to 108 , cell phones: 800 to 900 , Global Positioning System: 1227 to 1575 , microwave ovens: 2450 , wireless Internet technology: 2.4 to 2.6 . Which of the...

Hello, I'm doing a project on SBSP and we have a few months to complete it, and in my written report I will be going over NASA's data they collected from their attempts. Calculating efficiencies and otheer variables between different stages of transmission, e.g. first from the sun radi to PV...

Hi all, I am posting as a layman, whose 16 year old son has been issued with a court summons for criminal damage against a neighbour's car and driveway. A few weeks ago my son thoughtlessly emptied a small glass candle jar out of his upstairs bedroom window into what he thought was the...

Hi everyone, I'm going to be finishing the end of my third year in electrical / electronic engineering (my school doesn't have specialization until fourth year), and I am starting to realize that I am lacking in a lot of practical skills! (ie. soldering, hardware design, programming, general...

Hi everyone, I'm a grade 11 student in HS and am currently studying MV Calculus and Linear Algebra from distance learning through Stanford. Due to some problems, I'm going pretty slowly but I expect things to pick up soon. Anyway, I have an agreement with my school that if I complete a...

physics lab practical! (Centripetal Force) Homework Statement I need help to come up with a lab to figure out the centripetal Force of a cork as it rolls down the ramp. Homework Equations Fc=(mv^2)/rThe Attempt at a Solution i know that Fc= (mv^2)/r ,but i don't know if the velocity in the...

In the following two problems I am trying to get a deeper intuition of, the plane has 3 variables and is 3 dimensional and the hyperplane has four variables and is 3 dimensional as well. Can someone please show me why, practically, in the context of these problems? Question with hyperplane...

OK, let's try a little "applied physics". First, I like to race. Now that the season is over, it's time to use the cold winter to find more horsepower. While browsing through my large stack of science, engineering and physics books, I stopped with a copy of Schaum's Outlines, "Fluid...

"In fine weather, the electric potential increases with altitude at about 30 volts per foot (100 V/m)...." what hinders its practical application as a source of power, as a battery?

Hi guys. I have some questions about the practical use of a quarter wave transformer to match loads. For my question please refer to the figure below... According to my reading the input inpedance fo a quarter wave transformer is: Zin = Z12/ZL and to properly match the line with...

Alright, I did a lab today. Where I had to suspend a mass of 230g from a string attached to a Newton-meter between two clamp and stands. I also recorded values of angles. My question is for the calculations it says The equation F and θ is F= mg/sinθ + k where m is the mass of...

This is for a novel I'm writing. In it, the Earth has been separated from the Sun. At this point there is still an atmosphere (at perhaps 50% of normal pressure) but the temperature has fallen to somewhere around -150 centigrade. My question is this: Could a technologically savvy private...

Hi - I am a lay person with a practical question regarding sound. I live near a busy street and am considering having noise-reducing windows installed. The noise-reducing windows would fit beside (and in addition to) the current window to block out street noise, so in effect there would be two...

It's hard to convince people that they should hear and/or learn about the 4th dimension, string theory, and all of the like without giving them real world examples as to why these are all important. I've been trying to find a way to incorporate the 4th dimension in particular into a short...

I understand that spontaneous endothermic reactions are used rigorously in the design of instant cold packs to treat injures. Can someone please list and suggest other uses of spontanous endothermic reactions that can be used practically in everyday life

Suppose I have say a 40' long 3/4" garden hose stretched out linearly on a level surface. One end is attached to a faucet with maybe 30 psi. At 10', 20', 30', and 40' there are small vertical pipes from which will shoot water when the faucet is turned on. The end of the hose is capped. There's...

Practical detection of "similarity"? The world needs new mathematical ideas in order to solve the problem of making general purpose image recognition algorithms. What are some new ideas for approaching the problem of determining if two objects are "similar"? There are techniques for...

Hello, I have to give a presentation on an application of electromagnetic field theory of my choosing, and I was wondering if anyone had any suggestions that might be more interesting than the ones that have been suggested. It's for a 2nd year university level physics (E&M) course, so the...

I just enrolled in a physics MS program at a smaller state school. I am fascinated with physics and all other areas of science, but I want to get some really practical skills while I'm in this program. What are the most employable skills that one can acquire while studying physics?

Hi all. This is my first post so please forgive me if I write anything wrong or post on wrong forum. In the attachment below I have a problem. I need to buy a water pump (PUMPA in img) that works on 12 or 24 volt DC current being powered with solar panels. This pump must be able to fill a...

I was thinking that a car battery is a 12v source that delivers between 300 and 900 cold cranking camps. That'd put the cranking wattage at between 3600 watts and 10,800, right? Here's a car battery 'helper': http://goo.gl/Roo2l This is hypothetical at this point but what I was wondering...

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I just thought Id post some of my thoughts on what I feel is needed for undergrad physics majors who are interested in the more practical side of what we are learning in our highly idealized and theoretical coursework. I also would like to point out what tools I think are necessary for people...

1. The problem DIESEL IC ENGINE We were given a excel sheet, with RPM, Torque, Power, Bmep, Fuel mass flow rate, Airmass SFC, Engine Air inlet and Exhaust temp. The engine capacity is 2.2litre 4 stroke. Fuel specifications: 50 Cetane (0.05% Sulphur) Coolant = Fresh water with 45% glycol mix...

So I have a question that I have to answer that goes like: 1) Give some examples of practical situations where it is desirable to maximize the power delivered to the load. This is in reference to A.C Power analysis and understanding maximum power output is achieved when the the Thevenin...

Can this be done feasibly (with current/near term emerging technologies and sub-trillion dollar budget)? Assuming that the human race survives the 21st century, I think we'll have the resources for a multi-decade unmanned flyby mission to Alpha Centauri even if technology shows little progress...

Just an observation that I find interesting; I normally only participate in engineering threads, but I read threads from all these forums. I've also studied many mystical traditions, and am currently studying under a master in the Christian Kabbalah. I've noticed from these physics...

Homework Statement Hello, I now have a real practical mathematical problem to ask I have 14 files with different sizes to be burnt on DVD discs. Each DVD disc is 4.7GB. How to arrange the files so as to minimize the use of discs? The file sizes of the 14 files are 1) 2.25GB...

Okay, so I'm panicking cause I was supposed to give my draft in two weeks ago... and I haven't... Cause I got stuck... And began to procrastinate... Have started it again now... AND I'M STILL STUCKKKKK! So if someone could just give me the basic answers to these questions, I'll know I'm on the...

I have taken general chem 1&2 and orgo chem 1&2, but I honestly don't know how the chemistry I know relates or is used in anything. I can write page long synthesis and mechanisms, but I don't really know what I'm making, if it's safe, or if it's impossible. I only have one chemistry class left...

Hi guys , I don't know anything in electronics past how to calculate voltage and currents in circuits containing resistors and batteries . I lack the practical knowledge of how to construct real circuits . I want to know how to design real circuits . Can some one please point me to resources on...

I apologize for the rather vague title. It's space-limited and I'm not sure how to concisely state what I want to know. Basically, I understand that the solutions to quadratic equations (and if I remember correctly cubic equations) often had surveying problems land surveying. However, quartic...