Dynamic Definition and 431 Threads

I am attempting to construct the locus in the r,θ diagram of points of constant dynamic phase S~(t,θ) for t=0 and for values ofL~=4M,E~=1 I begin with Equation (27) in Box 25.4 which is: ##\tilde S = - \tilde E t +\tilde L \theta ## ##+ \int^r [\tilde E^2 - (1-\frac{2M}{r})(1+\frac{\tilde...

Dear all, I am currently going through the book called "Essentials of Structural Dynamics" and I have come to a parameter known as the Dynamic Load factor (DLF for short). I am having trouble understanding what this is and how you calculate it for a given problem. What's confusing is there are...

TL;DR Summary: Applied mechanics, mechanics, optimization, dynamics, kinematics Hi, I'm trying to finish this assignment and I'm not completely sure how to proceed. Should I first create the constraint equations, then the kinematics to get the derivatives for velocities and accelerations...

I have a doubt with the last part. Why isn't the right side negative? Because when the block is released, it moves upwards. thanks image was obtained from here Thanks.

In order to calculate the acceleration, I sum the equations sum fx^B and sum fx^A. F_{r,B} - m_Ag sin(theta) - (m_A+m_B) g sin(theta) = - (m_A+m_B) a then a = -[F_{r,B} - (2 m_A+m_B) g sin(theta)]/(m_A+m_B) =-[muk (m_A+m_B) g cos(theta) - (2 m_A+m_B) g sin(theta)]/(m_A+m_B) but the...

Hi! I have exam in couple of weeks , and now am looking for sources to learn about dynamic systems , chaotic systems and etc. My main goal is to learn characteristics of such systems , learn about special points in dynamic plane. For the most part we used to create dynamic system simulations...

TL;DR Summary: Why the topic give the condition "limρr^5/2=0“？What is the usefulness of this condition？ Thanks!

Can someone show that the instantaneous circle is indeed given by when the centripetal force is removed? This can be found at https://www.vedantu.com/iit-jee/circular-motion

Does anyone see a way I can find geodesics in the metric ##ds^2=-dt^2+dp^2+(5p^2+4t^2)d\phi^2## (ones with nonzero angular momentum)? I'm hoping it can be done analytically, but that may be wishful thinking. FYI, this is the metric listed at the bottom of the Wikipedia article about Ellis Wormholes.

TL;DR Summary: Have a university project where we are calculating the speed of the arm at the end. I need some help on where to start on the calculations. We have tried to determine instantaneous center of rotation for the device. We want to find the linear velocioty of point B. There is a...

My Raspberry Pi 4 has a GUI widget that is supposed to let us specify WLAN settings on a per-SSID basis, but it doesn't work. (All SSIDs end up with the same setting). Some articles on the net say that one can modify the dhcpd.conf file with an entry headed by the SSID name and then put in...

Been a long time I studied physics that had anything to do with mechanics, so I'm now in need of memorizing almost everything. So I am seeking for some guidance here. This is "system simulation/modeling/discrete event system simulation/etc" type of subject. The first thing that I didn't...

How to find the collision number if the moving bullet hits a few wooden blocks and every collision takes 10 percent of its speed. In which block will the bullet stay?

Summary:: In a mass-spring system they talk about 'magnitude of dynamic force', what is meant with that? Hi! In a mass-spring system I read about the term: "magnitude of dynamic force" (see sketch). What is meant with that? I the end this is used to determine the accuracy as I understand it...

Hi, I was doing some practice problems online for dynamical systems and came across the following question about isoclines. It left me with 2 questions that I hoping to get some insight to. Question: 1. What are isoclines? (I have tried doing an internet search, but the results don't help me)...

Homework Statement:: Can someone explain the finite number of equilibria outcome of the Poincaré-Bendixson Theorem? Relevant Equations:: Poincaré-Bendixson Theorem [Mentor Note -- General question moved from the schoolwork forums to the technical math forums] Hi, I was reading notes in...

In the solution manual, it says that: the resultant of friction force is ##<= kmg##, hence $$m\sqrt{\omega_t^2 + (\frac {v^2} {R})^2} <= kmg$$ and from this equation, we will get $$v^2 <= R \sqrt{(kg)^2 -\omega_t^2}$$ which will make ##v_{max}^2= R \sqrt{(kg)^2 -\omega_t^2}## Finally, they...

Hey! 😊 Classify the following statements according to static or dynamic integrity constraints, based on the database that is to be created in the thread https://mathhelpboards.com/threads/creating-tables-integrity-constraints.29157/. 1. A customer's discount may not exceed 50 percent. 2. The...

Summary:: Hi, this is an exercise from an algorithm course. I have been trying for hours but I have no successful ideas on how to solve it. I can only understand that DP is the correct approach, since Greedy method does not work. Suppose you have *n* friends that wants to give you an amount of...

Show that a point with acceleration given by: a=c*((dr/dt)×r)/|r|3 where c is a constant, moves on the surface of a cone. This is jut an example to illustrate my doubt. I don't know how to obtain the tracjectory given only the acceleration in this format. I realized that if i can show that...

Another user suggested adding the forces in the x and y direction then dividing by 1.4. Doing this for A) gave me 4.285 which was wrong any suggestions?

I tried A with the solution of 9.73 and 8.69 both wrong.

Here is where I am at : 1- F(C2/P) > F(C1/P) must be true I believe this is false, considering the angle separating C1 from the 'ceiling' is bigger 2- F(C2) > 10 N may be true I believe this is true because F(C2) could be broken down into vector components which may go above 10 N 3- Vector sum...

We all know that a flowing fluid acquires dynamic pressure as a result of this velocity. But the pressure has been known to be the kinetic energy of unit volume of flow i.e. 0.5 times density multiplied by the square of the velocity. I just want to know how to convert that into units that are...

$$\Box A_\alpha +\mu^2 A_\alpha = 2\beta A_\mu \partial_\alpha A^\mu + \frac {4\pi}{c} J_\alpha$$ where ##A=(\Phi, \vec A)## and ##J=(\rho, \vec J)## using a static configuration first where ##α=0## and then a dynamic one where ##α=i## knowing that ##E= - \nabla^2 \Phi - \frac {\partial...

I recommend this video. I'm very impressed by the engineering. 835kph, transonic effects, and 120G turns in a RC hobby aircraft; wow! From the video, I learned about aerodynamics, wind patterns around hills, the idea of dynamic soaring, airfoil design, controls coordination, ballast...

I set up this problem this way: ##p_a^{\mu}=(E, \sqrt{E^2-m^2}, 0, 0)## ##p_b^{\mu}=(m, 0, 0, 0)## ##p_c^{\mu}=(2E_\gamma, 2E_\gamma, 0, 0)## I have chosen to consider the two photons as a single particle of energy equal to ##2E_\gamma##. At this point I applied conservation of the...

Hi there could someone please help me with this question we have not been taught the content of this question what so ever so help would be very much appreciated. As you will be able to tell by the question it is not very difficult however I am not excellent at engineering or physics and...

Let's say we have a rectangular plot of two curves X(t) and Y(t); and next to it we have a parametric plot of (X(t) , Y(t)). Now we want to add a slider that can control markers on both plots, so that the slider ( = ts) moves two markers X(ts) and Y(ts) across the rectangular plot and at the...

Hi, I'm reading the following paper (L. Chua) about the state-of-art of dynamic non linear circuit analysis -- Chua_Dynamic_Circuits I've a doubt about Theorem 2 on section 3.2 On the Existence of the Resistor Function that establishes sufficient conditions for the existence of network...

In the example below, x is static while x1 is a dynamic copy of x. Also, y and z are similar expressions containing x and x1 respectively. If we evaluate expressions containing x and x1, they display in numeric and mathematical formats, respectively (y and z below). How can I display z as a...

Hi, in the books about the design of welded connection, we can find detailed description of calculations for static and fatigue loads. But what about the other type of dynamic behavior - shock ? As an example consider welded parts of the tow hitch used to free vehicles stuck in mud. Of course...

Photons have 0 rest mass. But could I talk about relativistic, or dynamic photon mass, that would be the solution of hf = mc^2 ? The relativistic mass would be m = m0/sqrt(1-v^2/c^2), where m0 is the rest mass, so 0, and v = c, so the denominator is also 0. The previous equations would give 0/0...

Hey! :unsure: At the cash register of a store we want to give change of worth $V$ cents of euro. Create and analyze a greedy algorithm that gives the change using the minimum number of coins. Assume that the available coins are the euro subdivisions, i.e. $\{1, 2, 5, 10, 20, 50\}$ and that we...

I am thinking of doing a DIY project in which one sub-task would be to dynamically balance a small assembly that will be spun up by, for example, a small motor taken from a DVD drive. As a test case, here is a setup where we would like to adjust screws S1 to S6 such that the cylinder is...

Hi I know that the equation of a simple harmonic oscillator is ##\ddot x + \omega^2 x=0##. The thing is that I don't know how to get to that equation in the situations given. In the first situation, I know that ##x) k(x-x_0)=m(\ddot x -x \dot \theta ^2)## ##y) N=m(2 \dot x \dot \theta)## So...

I know the acceleration of the rock is equal to g, but why. If we neglect air resistance, what is actually making the rock fall? Wouldn't it be that g overcomes the acceleration of the y plane at some point so the rock starts coming down or in this case accelerate more by throwing below 0 degrees?

I have studied arrows and arrow flight the best I can for a number of years owning an archery shop A number of years ago I began testing arrows in the shop which we refer to as a static test We look at straightness, deflection matching and weight matching We also test to find the stiffest...

Summary:: Having the following dates:

Hi everyone, I need help for this homework. I'm a mechatronics engineering student and i want to solve this question but no matter how hard I try, I can't solve the question. Sorry for my bad english...The disk connected to the AB stick with a length of 2 meters is rolled as shown in the figure...

I'm trying to dynamically model the scenario of a disease spreading across the population, modelling the number of cases, and I would love to hear your feedback. It's kinda different from the S-I-R model, and its also a crude model. First, we consider two numbers, NT and NA. NT is the total...

Hello! I am reading about excited levels in nuclei (I am mainly following Wong's nuclear physics book) and I am a bit confused about the nature of the excited states. In the one particle picture (mainly shell model) the excitation appears as static i.e. one nucleon moves from a certain orbital...

The main error in my earlier work was forgetting that to obtain ##\delta X## you have to find not only ##\frac {\partial X}{\partial g_{ij}}##, but also ##\big(-\frac {\partial X}{\partial g_{ij,k}}\big)_{,k}## and ##\big(\frac {\partial X}{\partial g_{ij,kl}}\big)_{,kl}##. I also missed a...

I am trying to run a calculation to work out the overall heat transfer coefficient of an arbitrary ten plate exchanger where the fluid is not determined using Re=puD/mu where mu is dynamic viscosity. When mu is such a strong function of temperature how should I determine which valye to use, say...

Hi ! This is my try: Is that correct ? Thanks

a) Our force can be represented as: $$\vec F= -k(r-H) \hat r$$ then the equations of motion are: $$\hat r: \ddot r -r {\dot{\theta}}^2=-\frac{k}{m_1}(r-H)$$ $$\hat{\theta}: r \ddot{\theta} + 2 \dot r \dot{\theta}=0$$ Plus we know that angular momentum is constant then $$|\vec L|=m r^2...

1) the motion equations for ##m_2## are: $$T-m_2 g=0 \rightarrow T=m_2 g$$ ##m_1##: $$T=m_1\frac{v^2}{r_0} \rightarrow \vec {v_0}=\sqrt{\frac{r_0 g m_2}{m_1}}\hat{\theta}$$ 2) This is where I am stuck, first I wrote ##m_2## motion equation just like before, but in polar coordinates...

Does anyone know a good book on master-slave schemes in dynamic systems? I'm on a dynamics book covering oscillators and it kind of glances over the topic and expects me to know it. I've done previous basic dynamics books and haven't seen it in them and checking on the internet I have found very...

Here, I have two doubts 1) if the surfaces are frictionless, then there's no force being applied on the ##x' axis## of ##m_1## except from the weight, so it should be sliding, shouldn't it? So, there's no force that I could apply to ##m_2## to keep ##m_1## in equilibrium since any force that I...

Hi ! I'm trying to understand why does we say that RLC circuit is a dynamic system. An example of a dynamic system that i know is a pendulum. The swinging of a pendulum depends on the applied force but also on the past force. What about the output of RLC circuit ? What is the relation between...