Planes Definition and 543 Threads

This problem is from Prof. Jaan Kalda's study guide to the IPHO. The problem can be solved by optimization, but there is apparently also a geometric approach, which is the one Kalda suggests. Initially I, being naive, tried to solve the problem by calculating the resulting distance the red plane...

I assumed the plate areas to be ##S## , then electric field at ##P## should be $$E_P=E_{+\sigma}-E_{-\sigma}=\frac{k\sigma S}{h^2}-\frac{k\sigma S}{(h+d)^2}\approx \frac{2k\sigma S d}{h^3}$$ but i think it's wrong here as ##P## lies at the edge , so it won't recieve electric fields in a way...

I just saw this coming in for a landing at Toronto International. https://www.dailymail.co.uk/travel/travel_news/article-10710607/German-airline-Condor-unveils-planes-painted-like-beach-towels.html

For this problem, The solution is, However, I could not get that. By getting the system in REF, I got ##x = 3 + \frac{3}{7}z ## and ##y = \frac{1}{7}z##. Therefore z is a free variable so ##x = 3 + \frac{3}{7}t = 0## and ##y = \frac{1}{7}t##. Thus equation of line is ##x\hat i + y\hat j +...

Suppose I have two intersecting planes in a four dimensional space. It seems to me that there are two angles between these planes. If the two planes intersect in a line then one of those angles is zero. If the two angles are non-zero then the planes intersect in a point. If one plane is the...

What I don't understand is how come the electric field of the negative plane isn't pointing towards the positive plane (in blue) and cancelling out the electric field of the positive plane (in red). See image

I looked at this question and i wanted to ask if we could also use; ##C## =## c_2 ##(##-\dfrac {3}{2}i## +## j - 3k)## ... cheers This problem can also be solved by using the approach of cross product ##A×B##...

I HAVE NO IDEA HOW TO START.ONLY THINGS I KNOW ARE WHAT I RERAD ON THIS THRED. https://www.physicsforums.com/threads/equilibrium-of-a-stiff-plate-on-inclined-planes.947601/I can't continue from there. There are also questions where α=β, α+β=45 and where α=45,β=60.How to make use of the fact...

The tail wheels on many WW II planes look tiny. How did pilots steer these planes when taxing? Was it by using the tail wheel? If so, what control was used to turn the tail wheel ? - some sort of steering wheel separate from the other flight controls?

I imagined the bar slipping along a virtual displacement, with the top and the bottom slipping by equal amounts. Since the planes are orthogonal, I took the components of these displacements: the lower end is displaced Lsinα in the direction of the right plane and by Lcosα in the direction of...

I have a problem as shown in the figure So assume there is a cylinder rotating inside a stationally wall. There is a viscous fluid in between the gap of cylinder wall and outer stationary wall, similar to bearing. The fluid has some velocity in axial direction also the outer wall of cylinder...

Hi! I have a question about inclined planes. In the diagram I attached, you can see that, with or without friction, mass does not affect the acceleration of the block. However, in my experience, the more people I put on my sled, the faster it goes. Why is this?

b) The Points on L1 satisfy the equations of the planes P1 and P2. The Points on L2 satisfy the equations of the planes P2 and P3. The Points on L3 satisfy the equations of the planes P1 and P3. Let v1 be a vector along L1 which lies on both planes P1 and P2. Let v2 be a vector parallel to v1...

All the materials that I have been reading, it says that when the element is rotated to a θ, this will be called the principle stress plane with no shear force acting on it. but visually when you rotate the element, there will be a shear force acting parallel to the plane. I am very confused...

I always thought that one independent equation cuts down the dimension by 1, so if we had two planes, say x - y - z = 1 and x + y + z = 1, then because these are two independent equations, the dimension of the intersection should be 1 because each plane is cutting down the dimension by 1. Using...

I am not sure about my free body diagram. I assume the cylinder rolls without slipping so the forces acting on the cylinder are: Weight directed vertically downwards Normal force directed perpendicular to the plane friction directed upwards, parallel to the plane Am I correct till this point...

First, I try to make a sketch and from that I take limit of integration from: 1. ##z_1 = 0## to ##z_2 = 4 - x -2y## 2. ##x_1 = 0## to## x_2 = 4- 2y ## 3. ##y_1 = 0## to ##y_2 = 2## Then, I define infinitesimal volume element in the first octant as ##dV = 1/8 dz dz dy##. Therefore, $$V=1/8...

Hi All, I am helping a student (9th grader) develop a research topic related to his interests in physics for an independent study program he is applying for at our school. My background is Geology, so I am not too knowledgeable regarding topics in physics. This student is interested in...

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Honestly no idea how to get an answer. I found the electric field between the planes and out of it in those two cases but this didn't take me very far. The final answer is E(B)/E(A)=2. Can someone please explain why?

So this "seemingly simple" geometry and idea caught my attention. See the video in the link from 9:00 minute They talk about a specially designed nuclear fuel canister/bundle, now there is this geometry where they have a cylinder with smaller diameter and then a cylinder with a larger...

Because the friction is the same in both parts, the calculated acceleration from (b) should be the same for (c) I knew I could find Vf, and thought I could do it with an energy equation Ei=Ef mgh=1/2mv^2 gh=1/2v^2 (2)9.81(1.5)=1/2v^2(2) (square root)29.43=(square root)v^2 v= 5.424 Then...

I determined 42m to be the hypotenuse so I used sine law to find the height of the incline, 10.87m. I used this height in the equation Ei=Ef, since they should be equal. Ei=Ef mgh=1/2mv^2 (at the start there is no kinetic energy, at rest. at the end there is only kinetic, no potential)...

Hey! :o Let an arbitrary linear system of $3$ equations and $3$ variables be given. There are $4$ cases how the planes can be related. Describe these $4$ cases graphically and describe the set of solutions in each case. I have done the following: If the three equations are linearly...

FIRST PICTURE I have some doubts here because of the spring... I'll tell you what forces I've drawn. For ##A##, I drew the weight and the force applied by ##B## (the normal force) on the vertical axis; and the elastic force pointing to the right on the horizontal axis. For ##B##, I drew the...

Homework Statement: Hollow cylinder balancing Homework Equations: F=m·r·(ang_v)^2 T=F·l Hi, I want to know how the hollowness of a cylinder would affect its balancing process. A little introduction: There are 2 different types of balancing: in a single plane (static balance) and in 2 planes...

So my problem isn't actually finding the components, but knowing if the initial approach I took is correct. So what I did was: At first I found that at the same instant, ##x_{B/A}=10500 m## so then I wrote the equation of motion for plane B respect to A: so $$\vec a_{B/O}- \vec a_{A/O}=\vec...

Dear experts, What are these things (dozens of them): Are these birds, planes or satellites, or meteors? Has anyone seen anything like these?

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Two planes, plane 1 and plane 2, intersect in the line with symmetric equation (x-1)/2 = (y-2)/3 = (z+4)/1. Plane 1 contains the point A(2,1,1) and plane 2 contains the point B(1,2,-1). Find the scalar equations of planes plane 1 and plane 2. I have no idea how to do it, all help will be...

Homework Statement Find equation of line of intersection of planes r.(3i-j+k)=1 and r.((i+4j-2k)=2 Homework Equations a x b gives a perpendicular vector to a and b...(i) The Attempt at a Solution to write equation of a line r=a+tb we need a point a on the line and a parallel vector b. Taking...

Homework Statement Two blocks of mass m1 = 3.00 kg and m2 = 6.00 kg are connected by a massless string that passes over a frictionless pulley (see the figure below). The inclines are frictionless. Image - https://www.webassign.net/serpse9/5-p-049.gif The inclined plane is shaped like a...

Homework Statement Let G be the region bounded by the planes x=0,y=0,z=0,x+y=1and z=x+y. Homework Equations (a) Find the volume of G by integration. (b) If the region is a solid of uniform density, use triple integration to find its center of mass. The Attempt at a Solution [/B] My...

1. Homework Statement This is an olevel question from paper 5090 may/june 2012 paper 12 question number 24 (the snapshot is from another question paper) the answer in the marking scheme is A which clearly I cannot understand. I thought shoulder joints have 3 planes of movementHomework...

My question is simple. Why do we need 9 different quantities, ie 1 normal stress and 2 shear stresses on 3 different planes, to define stress at a point? example: http://www.geosci.usyd.edu.au/users/prey/Teaching/Geol-3101/Strain/stress.html I think it should be enough to define the 3 stresses...

Homework Statement A thin stiff uniform rectangular plate with width L (L =AB) is lying on two inclined surface as shown in Fig. 3-1. The angle between the horizontal surface and the left inclined surface is α, and that between the horizontal surface and the right inclined surface is β. It is...

Homework Statement Find the value of the parameter α for which the pencil of planes through the straight line AB has a common plane with the pencil of planes through the straight line CD, where A(1, 2α, α), B(3, 2, 1), C(−α, 0, α) and D(−1, 3, −3). Homework Equations Let Δ be a line given by...

I want to calculate the volume of a sphere cut by two arbitrary plane. There is a intersection angle between these two planes, which is not 90 degrees. One of these two planes is fixed and located on plane "x-o-y", and the other is perpendicular to plane "x-o-z" and moves the distance "a" from...

Homework Statement The problem states: "A point charge q is located at a fixed point P on the internal angle bisector of a 120 degree dihedral angle between two grounded conducting planes. Find the electric potential along the bisector." Homework Equations ΔV = 0 with Dirichlet boundary...

Mod note: Moved from a technical forum section, so missing the homework template. @fab13 -- please post homework problems in the appropriate section under Homework & Coursework. I have the following exercise to solve : I have to find all the points on the surface ##x^2+y^2+z^2=36## (so a sphere...

Homework Statement Does the line with equation (x, y, z) = (5, -4, 6) + u(1,4,-1) lie in the plane with equation (x, y, z) = (3, 0, 2) + s(1,1,-1) + t(2, -1, 1)? Justify your answer algebraically. Homework Equations (x,y,z) = (x0,y0,z0) +s(a1.a2,b3) + t(b1,b2,b3) The Attempt at a Solution...

I have two 3D planes: A1*x + B1*y + C1*z + D1 = 0 and A2*x + B2*y + C2*z + D2 = 0. If you set them equal to each other it should be at the intersection. This leads to another Plane: (A1 - A2)*x + (B1 - B2)*y + (C1 - C2)*z + (D1-D2) = 0. What I want is the line of intersection in vector and...

Hi there, I am new to the Forum! I have a little bit of a tricky Problem. I am trying to calculate the Contrast between two planes as seen here: So I started by cutting the Problem in two Parts. Part 1, The Monitor: I know the Luminance of the Monitor X, and the reflectivity of the...

I know that planes have static dischargers (static wicks) on the trailing edges of wings to discharge static electricity when they are flying. I was wondering how a plane, let's say with electrically resistive fibreglass wings, would discharge this without having sparks ignite while it's...

On airplanes - do you know of a container or bag that will stops individual bottles with liquid from leaking/ exploding from the changes in air pressure?

So I'm watching a documentary on supersonic flight, and the challenges they describe seem SO daunting that I couldn't help but wonder: Wouldn't it just be easier to fly above (most of) the atmosphere? There must be an altitude where sonic booms no longer reach the ground and wind pressure no...