Dynamic Definition and 432 Threads

When I studied the fluid dynamic , I saw a quite hard equation (typed in attached file) , I don't know how to prove it , maybe there's a somehow relationship between this eq with Gauss's Divergence Theorem ... Can anyone help me ?

Should the static spring constant and dynamic spring constant of the same spring be the same value (or very close to the same value)? I know the difference between the two is that static is found by measuring the displacement from equilibrium by adding different weights and dynamic is found by...

I'm trying to conceptualize a design for a hydro generator that basically operates by moving an airfoil up an down along a straight path. Most of it is all worked out, except for the issue of water sealing. If you can make sense of my not-so-great drawings, the airfoil is attached to the...

a train of mass 240 tonne is moving, at a speed of 84 km/h, up an incline of 1 in 90. the resistance to motion is 45 n per tonne. if power is removed, calculate the distance traveled along the incline before the train comes to rest and a railway wagon of mass 10 tonne traveling due east with a...

Homework Statement A light spring having a force constant of 125 N/m is used to pull a 9.50 kg sled on a horizontal ice rink. The coefficient of kinetic friction between the sled and the ice is 0.200. The sled has an acceleration of 2.00 m/s^2. By how much does the spring stretch if it pulls on...

IMP! how to perform a dynamic thermal analysis on ANSYS? I have to simulate a model having an alumina pin on a rotating steel disc to calculate the surface contact temperature of the pin in ANSYS, and to give rotational speed to the disc LS-DYNA has to be used. But thermal analysis cannot be...

Homework Statement http://img689.imageshack.us/img689/2315/dynamicsproblem.jpg" Homework Equations The Attempt at a Solution FC = FfB mC * 9.81 = (6.0)(9.81)(0.30) mC = 1.8 <---- :( Obviously that was wrong haha. I then tried to figure out how the pulley affects the...

Hello, I have a little question regarding airflow. You have an object in a wind-tunnel, which has a dynamic pressure of 1000Pa and say static pressure of 99000Pa. If the object has a duct with static and total pressure probes, to maximise airflow through that duct, would you be looking for...

just wondering if someone could explain the difference between a static and dynamic collision is. I am trying to model a side impact crash between 2 cars and just wondering why it would not be accurate using a static collision. i.e. applying a static load on the door in an FEA

I completely made this question up because it's related to class and it will help me understand the lesson better and more. Explain the work of scientists and how they revolutionized scientific thought. Include Max Plank, Einstein and Michelson-Morley. The work doesn't have to be only about...

[b]1. Machanical Prinisiples assignment. Homework Equations Hi guys, i am a new member here, and am really looking for some help. My question is: A wheeled truck has a total mass when loaded of 1500 kg and is to be hauled up an incline of 1 in 1o (sine). g= 9.81 m/s2 and the...

I've read small bits of Tesla's Theory of gravity., but nothing in detail. Does anyone actually know how he explained the phenomenon of gravity? I know this is a vague question, and I don't know exactly what I'm looking for, but any information on the basis of why he rejected Einstein's General...

Gday fellow engineers, I have what I think is a rather trivial problem but would appreciate feedback on it. What I am working on is a mechanical model measuring the force of an object (eg a paddle pop stick or something else) along one axis of motion once a force is applied to it, causing it...

I'm interested in doing an experimental analysis of ribbon transducers to contrast with simulations. This data could be made available to the community to aid in transducer development. A ribbon transducer consists of a rectangular element of metal foil suspended within a magnetic gap and...

Hallo. I am new at forum, could please somebody send me a code for fluid dynamic in 3D written in Scilab, mathematica or Fortran. I will use it to start with learning!b Thaks, JG

hello. can anyone help me find information about "dynamic hardness measurements" ? a direction to books or websites will be very helpful... thanks

Homework Statement I am asked to provide an anti vibrational support mount for equipment mounted on turbo-prop aircraft. The equipment has a mass of 40kg. the vibrational response of the equipment to the environmental disturbances will need ot satisfy a safety limit prescribed by the...

From the stupidity that brought us the cordless jump rope, we have the shake weights. I'm sure you've seen/heard the jokes being made about the suggestive motion you make while using these. You might as well pickup a brick and shake it. https://www.shakeweight.com/ver5/index.asp

Homework Statement You go to a quick – fix garage to get your brakes worked on. When your tires are re – installed, the mechanic forgets to put the lug nuts on your tires. Although nobody gets hurt, a tire comes off your car when you are traveling fairly rapidly and it is able to roll...

Let us assume a dynamic system which has vector with 'n' components (which are non-negative integers from 1->n) at time t=1. In other words we have a permutation over 1->n at time t=1. Assuming time to be discrete, at any time time 't' , the system evolves such that there are 't' permutations...

Hi. For a project of mine, I need a motor that can dole out and pull in a wire at a constant speed under a dynamic load. The load will be anywhere between 20-500 lbs. The speed will be about 1 ft/sec. Any idea about how I can achieve this effect? Is a motor even the right way to go or should...

I'm looking to get a full solution to the Navier-Stokes equation to describe fluid flow through a pipe with moving surfaces. For now I am just concerned with a two dimensional system. The upper and lower boundaries are parallel to the x-axis. The surfaces of the boundaries move sinusoidally...

Homework Statement 2 kg ball revolves in a horizontal circle with speed of 1.5 m/s. knowing that L= 600 mm, determine (a) the angle that cord forms withe vertical (b) the tension in the cord i don't know how to put the figure but this problem is similarly like people...

Hi, I have some question about the full well capacity and dynamic range of the CCD camera. The following link lists some full well capacity and dynamic ragnes of some CCD cameras: http://www.andor.com/learning/digital_cameras/?docid=321 My question is how they obtain the electron numbers...

Hi, I am solving the following nonlinear dynamical system using Energy Balance Method (EBM*). My intention is to arrive at an approximate analytical expression for the frequency of oscillation and the excitation force. u''+u=A(1+2*u) with u(0)=u'(0)=0, where A is a constant (Physically it...

Homework Statement i need an idea from all forummers.i have to do dynamic case study which is focus on kinetics that study of the relationship between forces and the acceleration they cause and it's based on Newton's 2nd law of motion.it can be problems that occur in real life which caused by...

Geogebra is a free and multi-platform dynamic mathematics software for learning and teaching. Looks pretty good to me if you can't afford an advanced software program like Mathematica or Matlab.

Hi all, I am trying to understand the concept of dynamic and static pressures and would appreciate your help. I've got a nozzle flow setup, such that the flow is exhausting into atmosphere. Am I right in assuming that the dynamic pressure at exit (relative to atmosphere) is equivalent to...

Hi, I already have a static website, and now I am trying to design a dynamic website. I used Apache, PHP, and MySQL and setup on my computer (hostname = localhost) and tested my member directory database. It worked fine that I can add, edit and delete, and update the data from table. I...

Is it a huge daunting engineering task to create a very large dynamic o ring water seal (sliding up and down a shaft with ring on a mating surface) say about 50 or 100 meters in diamter? Would it be a good idea to make the ring and moving part a cube like shape so as to have a square seal...

Dynamic Soaring takes advantage of differeing wind flows separated by a thin wind shear boundary. Recently the record for radio control glider reached 392 mph (peak speed is over 400mph, but the convention is to measure the uphill return speed: http://www.youtube.com/watch?v=WaQB16ZaNI4&fmt=18

Hello, I enclose a jpeg of the circuit and two simulink jpeg files. The first mdl file - First Test circuit sucessfully models the circuit. The second one where I attempt to model the circuit from its state space equation does not. Can anyone help me to create a correct state space model...

I have a question about the nodal equations of BJTs - when analyzing a circuit to find out the input impedance, output impedance etc. is the term representing the intrinsic emitter resistance, Rbe (that is approximately 26mv/Ic) multiplied by the term beta+1? I'm looking at two references, and...

A car is rising an excerpt in slope of 2%, at a constant speed of 88,5 km/h. If the driver does not change the motion, or changing the pressure of your foot on the accelerator, which should be the acceleration of the car down the stretch of 3%?Answer 0,491 m/s^2

Homework Statement does any1 know how to make dynamic mesh on open foam? Homework Equations The Attempt at a Solution i can't find any yet.. thx

Show that the following process is dynamically impossible: A single photon in empty space is transformed into an electron and a positron. Hint: use conservation of momentum and energy for this problem I know a photon has no rest mass and therefore its energy is just equal to pc. However...

Hello everyone, im a 5th year student and I am doing my final project which consists on analyzing the scavenging process of a 2 stroke opposed piston engine, but I am having a hard time creating the UDF for the dynamic meshing thing. Could anyone please help me?

Hey guys, I am rather stuck with my work from College, I missed a bit of College as I was having treatment for Cancer, and so I missed a lot of work :frown:, but I'm desperately trying to catch up! If anyone could help me with my work, I would really appreciate it, thank you guys/gals!

I'm confused about dynamic resistance. The definition I've seen is Rd = dV/dI. Is it also ok to write it Rd = d(IR)/dI, so that Rd = R + I dR/dI ? I couldn't find a straightforward definition for dynamic resistivity at all … is it ρd = d(Iρ)dI = ρ + I dρ/dI ?

I am currently working on a project which involves me using a force sensor. So far I have tested the sensor statically. However, I need to calibrate it dynamically so that the output voltage can be used to determine a force in Newtons. I have done a bit of research so far and it seems that it...

Homework Statement A jet-powered flatbed truck has a crate of mass m, which is strapped down to the truck with a tension three times the weight of the box. Find the maximum acceleration without having the box slide. Us= .9, Uk=.7 Homework Equations Fun= SUM Fun= ma Ff= -(Us) Fn...

Hello, First time post long time lurker! I've got an interesting project I am working on which involves a few MechE subjects. The overall goal (for now) is to determine the drag force of a cylindrical cone headed object in sand under various pressures. The movement of the cylinder is the tricky...

Hey Just needed some help with analysis of vehicle loading in dynamic and static conditions.Basically what are the axial and radial loads acting on the axle/wheel in static and dynamic conditions? Accompanying formula would be helpful. How would i go about finding out the loads under static...

Hey guys, new user here. I had a question about a project I am working on with a professor. Unfortunately he does not have much experience with fluent but is a very intelligent and experienced person when it comes to the theory. So I am basically trying to develop a chart of the power...

I just realized that the standard "twin paradox" in SR is actually a purely kinetic effect. It is solve by the obvious assymetry of the twins and the time dilation. However, the acceleration is not really needed in solving the paradox, since a third person could carry the clock backward...

I was wondering if anyone could tell me about Tesla's Dynamic Theory of Gravity, I couldn't find much on it (I read that it wasn't ever published, which could explain why I haven't found anything). I did read that his theory was explaining gravity by using electromagnetism, which is fascinating...

Hie. I would like to know anyone who knows or have idea on design static and dynamic model for Semiconductor Optical Amplifier? Currently my lecturer ask me to design using Optisystem software which I quit blur on designing this models. Anyone who knows and help me please. Thanks in advanced..

There is boom crane with a bucket attached at the end. The angle of the boom "theta" is 60 degree. The weight of the bucket with a man in it is 200Kg. The mass of the boom is acting at centre of the boom (length of the boom is 10m) is 600 Kg. There is a cylinder attached to lift the boom 1m...

I was wondering if anyone knows the answer to this question: Homework Statement consider 2 blocks of masses m1 and m2. the block of mass m1 is resting on top of the block m2 which in turn is resting upon a horizontal surface. The coefficient of static friction between the 2 blocks is u1...

HELP!A dynamic question with friction Homework Statement Two blocks lie on a table as shown and are connected by an inextensible cord around a frictionless, massless pulley. A force F=50N is applied to the pulley. The coefficients of friction between the blocks and the table are mu(s)=0.20...