Plate Definition and 1000 Threads

Consider a capacitor with 4 parallel plates and 3 dielectric insulators arranged like this...+I-I+I- The insulator in the center has an equal amount of + and - charge on each side of it so shouldn't the electric field across this insulator be almost zero? If I constructed this capacitor with...

How many images does a zone plate produces when an object is placed infront of zone plate?

Homework Statement This isn't homework or coursework as such, but i thought it may be the best place to ask this question. The last time i posted in the other section it was deleted! Im considering the case of an electrode of finite width L in the x direction. The y direction is...

Hi A steel plate 2 cm thick is maintained at a temperature of 550 C at one face and 50 C on the other . The thermal conductivity of stainless stress at 300 C is 19.1 W/mK . Compute the heat transferred through the material per unit length ? Answer : - we have q = - k . A ...

Hi, The attenuation resulting from puting a signal into a parallel plate waveguide is dependent on the excited mode. Why does the TM mode have greater attenuation than the TE mode? I can see in the maths it 'works out' to be that, but what would be a more conceptual/physical reason? Is the...

Homework Statement A parallel-plate capacitor C , with plate separation d , is given an initial charge ±Q_{0}. It is then connected to a resistor R, and discharges, Q(t)=Q_{0} e^{-t/RC} 2 (a) What fraction of its energy Q_{0}^{2}/2C does it radiate away? Homework Equations The equations for...

Hello, For my setup I'm looking for a method to heat a small stainless steel plate (50x50x10mm(2x2x0.4 inches), AISI 304) to 900ºC (1652ºF). The plate is fixed onto the frame, so it can't be removed. I've found some induction heaters, but they were all too expensive. Anyone got some...

Hi, I think I'm missing something with how a parallel plate waveguide works. In the picture I've shown below, there intensity of the E-field change depending on how far across the waveguide it is. While I know that this has to happen in order for anything to propagate, I don't quite...

Homework Statement Will the following thin steel plate plasticly deform due to its own weight, what is the maximum deflection of the plate? Plate dimensions 0.25 cm thickness, 3.0 m length, 3.0 m width. The plate is supported on two ends, by a wall (welded). Homework Equations σ =...

1. The plates of a parallel plate capacitor are separated by a distance (4cm). A point charge of magnitude (q=2e) (3.2*10^-19 C) is fired horizontally through a small hole in the positive plate of the capacitor. The charge is fired with speed (8.5 *10^5 m/s) and, upon reaching point M (located @...

Homework Statement A parallel plate waveguide has perfectly conducting plates at y = 0 and y = b for 0 ≤ x < ∞ and -∞ < z < ∞. Inside that bound, the waveguide is filled with a dielectric with k as a propagation constant. The Green's function to be satisfied is \nabla^2G + k^2G =...

I'm working on a project where I know that force will be applied by a bolt pulled through a hole in the center of an aluminum plate for load testing purposes (2200 lbs, actual worst case max force around 1500 with a 1.5 times safety factor), the dimensions (27"x6.25"x?), and the material (5052...

We have a region Ω in ℝ^2 with a smooth boundary. There is a plate of shape Ω and clamped edges which is approximated by the following equation: $$\frac{∂^2u}{∂t^2}=-Δ^2u$$ $$u(x,t)=0\hspace{4ex} x\in ∂Ω$$ $$Du(x,t)\cdot\hat{n}=0\hspace{4ex} x\in ∂Ω$$ \hat{n} is the outward pointing unit vector...

Homework Statement Two square metal plates with sides of length 0.1 m are separated in vacuum by 10-3 m. Find their capacitance. Homework Equations C = Q/V For a parallel plate capacitor: C = E0A/L The Attempt at a Solution If A is supposed to be the length of the metal...

Homework Statement A circular metal plate of radius 0.2 m has 1010 excess electrons uniformly distributed over its surfaces. What is the magnitude and direction of the field just outside the plate near its center? Homework Equations E = kQ/r2 The Attempt at a Solution Starting with E =...

Consider the following solution to the steady state heat diffusion problem on an infinite y domain. \[ T(x, y) = \sum_{n = 1}^{\infty}c_n\exp\left(-\frac{\pi n}{\ell} y\right) \sin\left(\frac{\pi...

We have a square plate with length \(100\). Three side are \(0\) degrees and one side is kept at \(100^{\circ}\). I left \(T(100, y) = 100\) and the other than were zero. Small areas near the two corners must be consider excluded. So I took this as the corners at \((100,100)\) and...

Billions of years ago, something must have triggered rifts and the separation of the first landmasses into the first tectonic plates? Do we know what happened, when or how, and what Earth would have looked like at the time? Could water have played a part in this and to what degree? I'm...

Homework Statement How much charge can be placed on a capacitor with air between the plates before it breaks down if the area of the plates is 5 cm^2. Homework Equations C=\frac{Q}{\Delta V} C=kC_o C=k\frac{\varepsilon _o A}{d} Where "k" is the dialectric constant. The Attempt at a...

Homework Statement Find the moment of inertia of a rectangular plate of mass m, sides 2h and 2k , rotates about its diagonal. Homework Equations I= Ʃmr^2 The Attempt at a Solution I=Ʃ m(x^2 +y^2) , let 2h parallel to x-axis, 2k parallel to y-axis. I= m(x cosθ)^2 + m (y cos ∅)^2 where...

Homework Statement A uniform square plate ABCD has mass 0.8 kg and side length .8 m. The square is pivoted at vertex D and initially held at rest so that sides AB and CD are horizontal (see the diagram). After it is released, the plate swings downward, rotating about the pivot point...

I am setting up a system where a rectangular plate is heated by a set of heater cartridges, producing about 4000 watts. This plate is in free convection air. It is used to melt plastic at regular invervals. I am trying to model the system so we can estimate temperatures of the plate to...

Homework Statement An 800 g steel plate has the shape of the isosceles triangle shown in the figure. What are the x and y coordinates of the center of mass? https://www.physicsforums.com/attachment.php?attachmentid=13559&d=1208292919 Homework Equations x=1/M ∫ x dm [b]3. The...

Homework Statement An electrode with a varying voltage V = V0 + VACejωt is placed near a plate. The current output from the electrode is then measured. We want to find the relation between the current output and the amplitude of vibration. We can assume VAC is small relative to V0...

I am in process of designing a homemade capacitance sensor and I'd like to have an approximation of the resulting capacitance of the following geometry. The plates are placed on the outer surface of a food grade plastic cylinder. The distance z between their edges is many times smaller than the...

Homework Statement The space between the plates of a parallel plate capacitor is completely filled with a conducting slab.What is the capacitance of the system ? Homework Equations The Attempt at a Solution The capacitance of a capacitor when a dielectric medium is placed...

I am currently in the process of designing an end-plate for a heat exchanger. I know I can do what I am about to ask with FEA, but that is not feasible right now. Here are the design parameters: Shell and tube HX, Max operating Temp=1100 F, 59 1" SS 304 Tubes, staggered pattern, 12" Shell OD...

Hi, I get a whole bunch of extruded Al plates. Each of them is about 7" long by 3" wide and 0.08" in thickness. They are extruded parts and cut into 7" long on each pc. However they are coming out wrapped, not substantial but quite a amount that is out of our tolerance. They are wrapped close...

I saw this section somewhere in the forum: Picture 2 plates charged to a voltage V, w/ capacitance C. Of course Q = C*V. An electron is placed in between the plates & released, & it moves towards the positive plate. Said electron with its negative charge now adds to the positive charge...

[b]1. Two semi infinite conducting plates at right angles to each other, we bring in a charge q from infinity to point (a,b) what is the energy involved in doing so? Homework Equations coulomb's law and method of images in griffith. The Attempt at a Solution force can be easily...

Here is the question that a circuit with silver plate, i though silver plate will act as conductor but I can't the answer 1.333. If i assume it as insulator, i will get the answer 1.3333... why? Thanks for your help in advance.

Homework Statement Drawing of the Problem An electron rests on plate A and is accelerated by a 400V Plate (B). From there, Calculate the Maximum Voltage a 3cm plate (C) can be charged before the electron makes contact with the plate. Directly opposite Plate (C), is a +100V Charged Plate...

I was watching Nova: Fabric of the Cosmos, and there was a part where they were discussing Hendrick Cassimir's dark energy plate experiment. If the plates move, then that is work being performed, right? Isn't it conceivable that this energy is capable of being harnessed regardless of how much...

If you have an infinite non-conducting plate, the electric field just outside is equal to sigma / 2*epsilon. The electric field just outside a conductor is equal to sigma / epsilon. I understand both these results, but why is it than in the formula for the capacitance of a parallel plate...

Homework Statement How do you calculate the moment of inertia of a regular hexagonal plate of side a and mass M along an axis passing through its opposite vertices?Homework Equations Moment of inertia for a right triangle with an axis running along its base would be I = m h2 /6 where h and m...

Homework Statement Calculate capacitance of a parallel plate but of made up o two media!? The parallel plate capacitor in the figure below is quarter-filled with mica (εr=6). Its remaining ¾ part is filled with air. The total area of the capacitor is 10 cm2 and the distance separating the...

Calculate capacitance of a parallel plate but of made up o two media!? The parallel plate capacitor in the figure below is quarter-filled with mica (εr=6). Its remaining ¾ part is filled with air. The total area of the capacitor is 10 cm2 and the distance separating the plates is 2mm. Find the...

Questions about parallel plate size... Hi everyone, new member here and I apologize in advance if my questions seem somewhat amateur. Recently I've started learning about capacitors, electrostatics and electric theory in general. I guess I'm having trouble trying to wrap my head around the...

I have read that if we have an isolated positively charged conductor, we can increase itself capacitance by bringing an identical conductor close to it and then earthing it, so, that the second conductor develops a negative charge and thereby helps in reducing the net electric potential on the...

Homework Statement A long rectangular metal plate has its two long sides and top at 0°. The base is at 100°. The plate's width is 10cm and its height is 30cm. Find the stead-state temperature distribution inside the plate. Homework Equations ∇2T = 0 T(x,y) = X(x)Y(y) X(x) = Acos(kx) +...

Hello All, I have a fixture that is used for lifting an engine. See attached image for the part in question. You can see in the 'front' view the hole where a pin passes through the part and the lifting lug of the engine. You can also see the loading. We want to machine the part down such...

can anyone tell me what formulae i can use to calculate the temperature of two plate? eg i have a cement plate on top of a steel plate. each plate say 0.5cm thick. on one side of the cement plate is at 1000 degree c. in still air of room temperature 20 degree c. what's the temperature of the...

Homework Statement Two plates of equal area: length b, width w On one side, the plates are a distance d away from each other, on the other side, a distance d+a Homework Equations No equations given. Using E= kq/r^2, V=-∫E*dl The Attempt at a Solution E = kq ∫∫dxdz/(x^2 +...

Homework Statement A flat plate lies in the region: 0<x<35, 0<y<inf The temperature is steady (not changing with time), and the boundary conditions are: T = { x if 0<x<35; y=0 70-x if 35<x<70; y=0 0...

Hi, I am trying to think of a way to attach my water baffle/cold trap to the bottom of my base plate. The baffle is attached to a diffusion pump, meaning that I need a good seal between the plate and the baffle. I was thinking about drilling holes in the baffle and half way through the base...

Homework Statement The right-angle bar with equal legs weighs 6.0 lb and is freely hinged to the vertical plate at C. The bar is prevented from rotating by the two pegs A and B fixed to the plate. Determine the acceleration a of the plate for which no force is exerted on the bar by A either B...

Is it possible that a planet's core could cool just enough to have the plate tectonics stop working without compromising the ability of the magnetic field to block off cosmic rays? I apologize if this question is in the wrong category, specifically I'm looking for the answer based on Earth or...

I was trying to calculate the the charge distribution (surface charge density = σ in function of r) in a very long circular metallic plate. I know σ not constant if we get closer to the rim of the plate Let's say we want to calculate the E field in point Q that is x distant from the center...

Homework Statement A force F is exerted on the top right corner of a rectangular plate at an angle 60o above the horizontal, as shown below. The magnitude of the torque of the force F about point A, the lower left corner is given by See picture please ...

Homework Statement So I need to identify the optical filter with jones matrix A=\frac{1}{sqrt{2}}e^{-i\pi /4}\left[\begin{matrix}1&-i \\ -i&1 \end{matrix}\right] Homework Equations See attempt The Attempt at a Solution So I have applied the rotation matrix like this ...