Static Definition and 1000 Threads

What is the magnitude of the static charge induced on a circuit board when a human touches it? I mean approximately.

1. Homework Statement A fresh water storage tank in a factory is shown in the figure above. Its top side is denoted as C, the narrow side as B and the long side as A. In order to allow regular maintenance and cleaning side A is hinged at its bottom edge and secured using a heavy-duty clasp at...

In Weinberg's book it is said that a Static, Isotropic metric should depend on ##x## and ##dx## only through the "rotational invariants" ##dx^2, x \cdot dx, x^2## and functions of ##r \equiv (x \cdot x)^{1/2}##. It's clear from the definition of ##r## that ##x \cdot dx## and ##x^2## don't...

hi guys, i am new user on ansys i have task from my lecturer. it is about static test for seat bus. i try simulate the seat bus on ansys statical structural. you can see my model on attachment (untitle1.png). at that picture, there are 2 bars will push the seat back. the stiffness beahvior of...

I have to make a project for school, so I thought that i can make a static electricity car. I wanted to make a car, and stick/put a material behind the car which creates a charge, and then take another material which creates a charge, and rub it. As it creates static electricity, the cars...

I know a real test of this unit would be to mount it and run, checking DC and AC voltage, current etc. The plan is to mount it on my Super Dexta, but this would need some work as there's currently a dynamo which is starting to fail. I was given the alternator free and would like to bench test it...

Good evening, Today's planes' need bleed air to start. Above a certain speed, igniters fire up and we inject fuel inside the combustor chamber. Why do we need to have the engine running to inject fuel (around 20%N2)? Can we simply not inject fuel with static air (i.e. when engine is not...

Homework Statement A shaft is being used as a cantilever and is held in the housing by its fit. It is to remain static whilst a gear is attached to the free end, how to you retain the gear on the free end of the shaft? Sketch a suitable method Homework Equations n/a The Attempt at a Solution...

I'm working with data across an airfoil and need some help. We've got Kulite sensor data along 3 chord lengths of a certain NACA airfoil. The case is of an incompressible flow. I need to determine the coefficient of pressure at these sensor locations using total pressure measured and I...

A customer of my employer emailed me with some requirements for a new machine that they plan to build. Everything was fine until I got to the part of the static shock load requirement of 2700in-lbs. A static load is a force/load put on for a long period of time, but shock load is a sudden or...

Homework Statement A 50kg object begins at rest on a surface with a static coef of friction at 0.6. If you push horizontally on the object with a force of 27N, how quickly will it move across the surface? Homework Equations The Attempt at a Solution[/B] This is from Trivium Praxis test prep...

Consider an infinite homogeneous static universe with a constant mass density $$\rho$$. If we were to calculate the force on a test particle located at a certain point accoring to Newtons law of gravity. It would be logical to conclude from a symmetry argument that the force on the particle...

Problem : A car of mass ##m## is parked on a slope. What does static friction ##\mu_s## have to be for the car not to slide down if the incline of the hill is ##30## degrees? ******* For this problem I have the following forces, where the hill is inclined upwards to the right: Upwards ...

Hello can someone explain the difference between static and hydrostatic pressure in terms of a water in a glass

In my experiments, on a flat plane, when I incrementally increase the normal force acting on a rubber block, I am measuring a decrease in the static coefficient of friction. I am also measuring the friction force, which increases as normal force increases BUT this is not a proportional increase...

Hi! I'm trying to complete a static force analysis on the bar linkage shown below. The goal is to find the payload mass in terms of the cylinder forces and everything else in a static environment. To simplify things I've made the assumption that the mass of the payload in the bucket acts at...

Hello, I am trying to solve an issue which occurs when two robots with different static charges make contact. It has been some time since my Physics classes and I have some ideas that are only partly making sense to me. I need to minimize the effect that a static shock is having on a small...

So according to classical electrodynamics, an electron would produce an electric field that is a physical entity in and of itself. This field has momentum so when a test charge is placed within this vicinity, it would be affected by the field itself, not the electron. But what about the QFT way...

Hi there, I was thinking that static friction works in opposition to a reaction force like the force of a fridge against you as you push it. However, since you are pushing horizontally and friction works against you why is it equal or greater than the reaction force? Will the force get...

Hi all, I have a doubt that I would like to solve with oyu help. Basically I want to calculate forces on a solenoid due to the magnetic field it produces and than calculate deformation. I consider 2 cases: 1/ Static I did analytic calculation for force calculation, and i made FEM simulation...

Hello, I have been learning about energy and work in my 100 level physics class and I got to thinking: W = F*d But I'm wondering how this works in the case of static friction. For instance, if I take a really heavy object and apply a force to it that isn't enough to move it, the distance it...

Homework Statement [/B] In an automatic materials handeling operation, metal blocks of 1.5 kg each are pushed one at a time from bottom of a stack six blocks high. If the coefficient of friction is 0.25, determine the horizontal force required to push. There is a figure bellow. I try to...

In a classic problem where a man walks along the length of a boat floating on the surface of water without friction, Should the net work done due to static friction between the man and the boat be zero. If the length of the boat is L, its mass being M, and the mass of the man being m, the...

Question: A large box of mass M is pulled across a horizontal, friction-less surface by a horizontal rope with tension T. A small box mass m sits on top of the box. The coefficients of static and kinetic frciton between the two boxes are Us and Uk. find an expreeion for the maximum tension Tmax...

Trying to wrap my head around how to calculate the energy/power expended when doing static exercises (i.e. static hangs from rings or handstands etc.) for various intervals... How do I relate the impulse (between myself and the rings or surface) to the total energy or work performed in say...

Homework Statement If the load on the uniform beam shown below is moved to the left, how do the tension force T and the magnitude of the vertical force Fv exerted by the wall on the hinge change? The answer is A Homework Equations torque = Fdsin(theta) The Attempt at a Solution My equation...

I have a 3 pulley system statically balanced hanging weights at a determined relative angle (we are taking into account friction). If I change the position of one pulley, angles will remain the same. However, if I have a 4 pulley system, at the same conditions, changing one's position will...

Homework Statement This is a real world application. I am posting it here to follow the guideline for any "coursework-like" questions, but since I have no formal training, I'm not sure what category this would actually fall under. Any recommendations for a more specific posting location would...

I've recently been developing a lot of static electricity and it's very annoying as I get shocked when i touch metal objects or other people. This isn't like it happens every time I touch something though. It just happens after I take off my jacket for example. So then I have to find some metal...

Though I am definitely not an expert in any way in QM, I understand that on a basic level quantum systems can be solved using schrodinger's equation. For a hydrogen atom, the wave function of the electron is found by using the hydrogen proton as an external potential and proceeding from there...

Hi all great PF members, Can anyone help me to sizing fan static pressure strong enough to open a metal cover an angle 15 degree at the end of the duct (20m in length with few 90 degree bends), I'm really not good at math so any help are greatly appreciated. Please refer to sketch attached for...

Hello dear friends, today's question is: In a non static and spherically simetric solution for Einstein field equation, will i get a non diagonal term on Ricci tensor ? A R[r][/t] term ? I'm getting it, but not sure if it is right. Thanks.

Homework Statement A block sitting on a flat surface has a us of 0.5. The normal force acting on the block is 10N. If someone pushes the block with a horizontal force of 2N. What is the static friction force acting on the object? Homework Equations F=ma fs=usR (less than or equal to)The...

Is food waste attracted by the static electricity?

Homework Statement A 55.0-kg box rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.300. A force of 156 N is applied to the box directed at an angle of 18.0 above the horizontal. Does the box move? Please help??The Attempt at a Solution 156...

This is all related to GCSE content, but it doesn't go into enough depth for it to make sense: When a balloon sticks to a wall after becoming negatively charged, why does the surface of the wall become positively charged? I would assume that the repulsion between negative charges forces the...

Homework Statement If the incline of the driveway is 19 ∘ from the horizontal, what must the minimum coefficient of static friction be between your shoes and the ice? Homework Equations Fs=uN The Attempt at a Solution

Hi folks, I have a pressure sensor working with arduino to measure depth. I want to calculate what I should see as a change in pressure if I move the tube horizontally under the surface of the water, keeping the tube opening parallel to the flow. I have calculated the dynamic pressure but...

I'm testing a part for fatigue, and I got a time series of Forces and Moments on three different parts of the body (A wind turbine hub). From the static structural fatigue analysis, I noticed that you need a von mises stress input - that's not a problem. My problem is, how do I place different...

Homework Statement A board that is of length L = 6.0 m and weight W = 335.7 N rests on the ground and against a frictionless contact at the top of a wall of height h = 2 m (see figure). The board does not move for any value of greater than or equal to 65 degrees but slides along the floor if...

Homework Statement Which cases are examples of static equilibrium? 1. A box sliding down a ramp. 2. A baseball after being hit. 3. A box sliding along a horizontal surface. 4. A perfectly upright freely spinning top 5. A freely swinging simple pendulum 6. A spinning astronaut floating out in...

Hey so I am learning physics on Khan academy and they had a video on Pitot tubes: https://www.khanacademy.org/science/physics/fluids/fluid-dynamics/v/venturi-effect-and-pitot-tubes I had a question. I understand that the lower part of the pitot tube in the video is measuring the pressure...

Allo, Recently, I have been researching RAM, including formats such as DRAM and SRAM. While I was running simulations on SRAM one week, I realized I could make a 1 bit Static Memory Cell using a simple Schmidt NAND IC. I ran a draft for it displaying two feed backing NAND gates as inverters...

Homework Statement 2 Blocks connected by a string is placed on a rough horizontal floor,the coefficient of friction for block 1 is 0.2 while for block 2,it is 0.1. A force of 8N is applied on block 1 and a force of 1N is applied on block 2.Find the tension in the string and the frictional...

In the tablecloth trick, if we pull the tablecloth with a great force, the objects on it will stay on the table. But, if we pull it gently, the objects on it will still get along with the cloth movement. I know that if the force exceeds the maximum value of static friction, the objects will...

Homework Statement How would I find the X coordinate of point A. So far I have: A: ( X=? Y=-231.125" Z=175") B: (X=0" Y=0" Z=144") https://physicsforums-bernhardtmediall.netdna-ssl.com/data/attachments/90/90134-44f7db5f8e2c5989352d374160952d17.jpg Homework Equations...

Homework Statement A uniform vertical beam of mass 40kg is acted on by a horizontal force of 520N at its top and is held, in the vertical position, by a cable as shown. a) Draw a free body diagram for the beam, clearly labelling all the forces acting on it b) Calculate the tension in the cable...

If you were to look at a simple 2D or 3D static equilibrium diagram, where a mass is suspended by multiple ropes at different angles, my gut feeling is that there is a fairly simple proportion between the distance between the center of mass and the rope (the distance created opposite of the...

Hello all I'm trying to calculate a torque needed to tighten a threaded terminal. (Both male and female parts are copper alloy) I'm using Motosh's equation which requires me to use the coefficient of friction. Web sources tells me that the copper-copper coefficient of friction is 1.0. The...

Homework Statement A rigid wire frame is formed in a right triangle, and set in a vertical plane as shown. Two beads, of weight W1 = 1.5 N and W2 = 2.5 N, slide without friction on the wires, and are connected by a cord. When the system is in static equilibrium, what is the tension in the...