What is Rectangular: Definition and 477 Discussions

In Euclidean plane geometry, a rectangle is a quadrilateral with four right angles. It can also be defined as: an equiangular quadrilateral, since equiangular means that all of its angles are equal (360°/4 = 90°); or a parallelogram containing a right angle. A rectangle with four sides of equal length is a square. The term oblong is occasionally used to refer to a non-square rectangle. A rectangle with vertices ABCD would be denoted as ABCD.
The word rectangle comes from the Latin rectangulus, which is a combination of rectus (as an adjective, right, proper) and angulus (angle).
A crossed rectangle is a crossed (self-intersecting) quadrilateral which consists of two opposite sides of a rectangle along with the two diagonals (therefore only two sides are parallel). It is a special case of an antiparallelogram, and its angles are not right angles and not all equal, though opposite angles are equal. Other geometries, such as spherical, elliptic, and hyperbolic, have so-called rectangles with opposite sides equal in length and equal angles that are not right angles.
Rectangles are involved in many tiling problems, such as tiling the plane by rectangles or tiling a rectangle by polygons.

View More On Wikipedia.org
Recent contents Top users
  1. K

    Moment of inertia for rectangular prism

    I want to find the moment of inertia (a formula) for a beam rotating around the center of a face. In other words, if I'm using http://www.engrasp.com/doc/etb/mod/util1/solidprop/sp005_rectprism/rectangularblock.gif", then I want to find its moment of inertia if its rotated about the POINT Zc, as...
  2. maverick280857

    Force on Walls of Rectangular Potential Box by Particle Inside

    Hi everyone.. I'm trying to prove the following proposition: The force exerted on the wall perpendicular to the x-axis by a particle of mass m contained in a rectangular box of dimensions a, b, c is given by the negative of the expectation of the derivative of the Hamiltonian wrt a: F =...
  3. S

    Open Channel Flow (mannings equation) rectangular section

    A rectangular concrete-lined channel is 2m wide with Manning's n 0.012 and a bed slope of 0.0025 m/m. Obtain the depth of flow when the discharge is 9m^3/s. Q=V.A I have the discharge but how do I calculate the velocity without the area ?? Once I have the velocity I should be able to work it...
  4. G

    Which is the area of each faces for the rectangular prism.

    Homework Statement Considering a rectangular prism bounded by six rectangular faces (x=2, y=0.5, z=1) and a cylinder (r=0.5, heigh h=2) that cut the rectangular prism in x=1 y=0 and z=0 with a inclination of 45 grads in y and z. Which is the area of each faces for the rectangular prism. I...
  5. D

    Manage rectangular cloth for square table

    How will you get a table cloth of 12x12 units for a square table from a rectangular cloth of size 16x9 units in a single cut and placing two pieces together ?
  6. F

    Optimizing Heat Loss in a Rectangular Building

    Homework Statement A rectangular building is being designed to minimize heat loss. The east and west walls lose heat at a rate of 10 units/m^2 per day, the north and south walls at a rate of 8 units/m^2 per day, the floor at a rate of 1 unit/m^2 per day, and the roof at a rate of 5 units/m^2...
  7. P

    Induced emf in a Rectangular Coil

    Homework Statement A rectangular coil of 150 turns has dimensions of 23 x 70 cm and is located in a uniform 3 T magnetic field. In 1.2 s, the plane of the coil is rotated from a position where it makes an angle of 15° with the magnetic field to a position where it makes an angle of 72°...
  8. D

    Spherical Coordinates to Rectangular Coordinates

    A particle of mass m moves in a "central potential," V(r), where r denotes teh radial displacement of the particle from a fixed origin. a) What is the (vector) force on the particle? Use spherical coordinates. We have F = -\nabla V = -\frac{\partial V}{\partial x} \hat{i} -...
  9. N

    Electric Field Due To a Rectangular Charged Wire

    Hi guys, here's a question i thought i knew how to solve but somehow it doesn't work. been trying and trying for almost a week :-( here it is: "A thin wire is bent in the form of a rectangle with length l = 12 cm and width w = 10 cm. The wire is charged up to a uniform charge density of...
  10. T

    Converting from Polar to Rectangular

    Homework Statement Convert r=3/(4cos\theta-sin\theta) to rectangular form Homework Equations r=\sqrt{}x^2+y^2 The Attempt at a Solution 4x-y=3 ?
  11. S

    Changing polar equations to rectangular equations?

    changing polar equations to rectangular equations? Can somebody please explain to me, how I would convert: ?=?/2 into a rectangular equation? Along with: r=sin?, r=6cos+sin?, r(squared)sin2?=2 Your help would be greatly appreciated!
  12. V

    CG of Rectangular Frame with Offset Weight: Need Counterweight?

    Hi, I had a question on CG. I have a rectangular frame (say made of square tubes) and have a weight fastened to its lower arm (as shown in the attached pic.), which is not fastened on the center of the lower arm but is offset. however, the CG of the weight is in the same line as the pick...
  13. C

    Upper cutoff frequency for rectangular waveguide

    So I know there is an upper cutoff frequency (at least in the microwave band) for a rectangular waveguide. However for the life of me I can't find why one would exist in the equations, the internet is full of references to it based off of the dimensions of the waveguide, but I'm curious whether...
  14. D

    Magnetic Field in a Rectangular Conducting Loop

    [SOLVED] Magnetic Field in a Rectangular Conducting Loop Homework Statement Figure 31-64a shows a rectangular conducting loop of resistance R = 0.010 , height H = 1.5 cm, and length D = 2.5 cm being pulled at constant speed v = 55 cm/s through two regions of uniform magnetic field. Figure...
  15. D

    How Is EMF Induced in a Rotating Rectangular Loop?

    [SOLVED] Emf in a rectangular loop Homework Statement A rectangular loop (area = 0.15 m^2) turns in a uniform magnetic field, B = 0.16 T. When the angle between the field and the normal to the plane of the loop is pi/2 rad and increasing at 0.70 rad/s, what emf is induced in the loop...
  16. B

    Triple integral over a sphere in rectangular coordinates

    Homework Statement Evaluate the following integral: \iiint \,x\,y\,z\,dV Where the boundaries are given by a sphere in the first octant with radius 2. The question asks for this to be done using rectangular, spherical, and cylindrical coordinates. I did this fairly easily...
  17. O

    Rectangular coil current problem

    please, i want to be sure of my password and user name can it be posted to email? also, idon't know how to submit questions can the guide lines be posted as well? Thank you. A rectangular coil, carrying a current of 400pie amperes, lies in the z=0 plane with its corners at the points...
  18. R

    Converting a number to rectangular form

    Find the rectangular form of the complex number z=a+bi which has modulus 2 and principal argument theta = -pie/6 2cos(-pie/6) to get length of x =sqrt3 What is the method used to get an answer in this form instead of decimal form (1.732) ?
  19. C

    What is a suitable thickness for a spinal disc implant endplate?

    rectangular plate bending... I am designing an endplate for a spinal disc implant as shown in the image below. http://img155.imageshack.us/my.php?i...ndplatenb5.jpg" I need to determine a suitable thickness of plate h. I thought about looking into winkler foundations to begin with but i...
  20. T

    Rectangular Membrane Metal Gauge Design: Research by Thangamani

    Dear Sir, This is Thangamani, doing research on sensor design. I have gone through Mr. Robert Dean (RF CMOS Designer, MEMS Optical, Inc) article that available on internet ( if not mistaken its from MEMS forum) discussed analytical solution about rectangular membrane. Since i am...
  21. R

    Rectangular sheets, angular velocity time?

    Homework Statement Two thin rectangular sheets (0.26 m 0.35 m) are identical. In the first sheet the axis of rotation lies along the 0.26 m side, and in the second it lies along the 0.35 m side. The same torque is applied to each sheet. The first sheet, starting from rest, reaches its final...
  22. M

    Angular momentum in a rectangular box

    This is more of a conceptual question. I'm looking for a "physical argument" as to why the angular momentum of a classical particle about the center of a 3d box wouldn't be conserved, as opposed to spherical well in which orbital angular momentum is a constant.
  23. E

    Comparing Circular vs Rectangular Diaphragm Strain Gage Pressure Transducers

    I am currently trying to learn about pressure transducers. There are two configurations which have been suggested for a particular pressure transducer -- 1) a circular diaphragm strain gage and 2) a rectangular diaphragm strain gage. Each configuration has four strain gages. For 1) there are...
  24. N

    Rectangular Optical Wavguide - EM Wave

    Hello All, this is my first post, and while I'm a newb to the forums I'm not a newb to Optics. However, I have a very light background in low level electromagnetics, I'm more of a network design person. I'm working on a very very long term personal project to understand optics better and I've...
  25. R

    Calculating Rotational Inertia of a Rectangular Prism

    Homework Statement There is a rectangular prism of uniform mass distribution with lengths of a, b, and c (b>a>c). Calculate it's rotational inertia about an axis through one corner and perpendicular to the large faces.Homework Equations I = \int r^2 dm r^2 = x^2 + y^2 + z^2 \rho =...
  26. C

    Convertong polar equations to rectangular eq.

    Homework Statement (theta)= 45Degrees Homework Equations (theta)= Arctan(y/x) (x>0) (theta)= Arctan(y/x) (x<0) The Attempt at a Solution Tan(45)=y/x 1 = y/x Does that mean Y = X? :confused:
  27. A

    Stress Concentration around a circular hole on a flat rectangular plate

    Can anyone help with how to find the analytical solution to problem involving finding the stress concentration around a circular hole in a flat plate. The plate is has tensile load on both sides.
  28. C

    Particle in a rectangular box.

    I am missing something. The question is to find the 6 lowest energy states of a particle of mass m in a box with edge lengths of L_{1}=L, L_{2}=2L, L_{3}=2L. The answer gives E_{0}=\frac{\pi^2\hbar^2}{8mL^2}. I would have said E_{0}=\frac{3\pi^2\hbar^2}{4mL^2} . What am I missing...
  29. V

    Why are paintings put in rectangular frames?

    If paintings were not put in rectangular frames but in triangular or hexagonal or circular frames what difference would this make to the end product? Would the artist be forced to think differently?When the Romans came to the United Kingdom in the first century AD they brought the idea of right...
  30. J

    Solving the Two-Cut Rectangular Cake Puzzle

    Warning: I do not know the answer to this one. If this will keep you up at night, do not read on. I was asked this in a job interview a long time ago. They did like my answers, even though they were "wrong". Still here? OK. You are presented with a rectangular cake. Somewhere at an...
  31. B

    Magnetic Field of wire on rectangular loop

    Homework Statement I have attached a diagram. In case you can't view it, it shows an infinitely long wire I_i = 5.00 A on the positive y direction. 0.100 m to the right, there is a rectangular loop of dimensions 0.150 m x 0.450 m, the long side is parallel to the infinitely long wire to its...
  32. A

    Electromagnetism - Magnetic flux between infinite wire and rectangular loop

    Homework Statement The figure shows a rectangular wire loop, around which a current I flows, and and an infinite straight wire. The wire lies in the plane of the loop and is parallel to, and a distance d from, the side AB. (see attachment) Show that the amount of magnetic flux generated...
  33. P

    Give answer in rectangular form

    Homework Statement Find the quotient w*u, w/u, w^2 w=3(cos30 degrees + isin 30 degrees) u=2(cos 60 degs + isin 60 degs) Give answer in rectangular form.. The Attempt at a Solution I can convert polar to rectangular and back.. but trig to rectangular? Eh? I got w*u=6i... I think that...
  34. J

    How to Calculate Transmission Coefficient for a Quantum Rectangular Barrier?

    Ok, so I've been dealing with this problem for a while and can't figure it out. (I tried to clean it up, but I don't know LaTeX, hopefully it is more clean in post #2; problem stated in #1, and my work in #2) --Consider a (plane-wave) particle tunneling through a rectangular barrier...
  35. S

    Calculate Baseboard & Carpet Needs for a 3.5m x 6.526m Room

    A rectangular room is 3.5m by 6.526m a. If baseboard molding is to be obtained to go around the perimeter of the room, calculate the correct amount that must be purchased. b. How much carpet must be purchased to cover the area?
  36. T

    Electric Field due to Rectangular Sheet

    Homework Statement Find the electric field due to a rectangular plate with charge Q, length L, width W, at a distance s<< L perpendicular to the plate. The point at that location is exactly above (with respect to the plate) the center of mass of the rectangular plate Homework Equations...
  37. E

    Magnitude in a rectangular loop

    Homework Statement The rectangular loop has a mass of .15 g per centimeter of length and is pivoted about side ab on a frictionless axis. The current in the wire is 8.2 A in the direction shown. Find the maggnitude and direction of the magnetic field parallel to the y-axis that will cause...
  38. J

    Circular apertures in rectangular waveguides

    I wish somebody could tell me if he knows articles or information about modeling circular apertures in a transverse metalic plate in a rectangular waveguide. It appears in the "Waveguide Handbook" by N. Marcuvitz, on page 238. Can anybody help me to find more information about this theme? Thanks...
  39. S

    Interference of rectangular pulse

    Question Details: The figure shows two rectangular wave pulses traveling toward each other on a stretched string. Each pulse is traveling with a speed of 1.00 mm/s, and has the height and width shown in the figure. If the leading edges of the pulses are 8.00 mm apart at t = 0, sketch the shape...
  40. S

    Surf area of sphere thru rectangular FOV

    I have a rectangular field of view (FOV) through which I am viewing a sphere at a distance such that I can only see small parts of the sphere through the FOV at a time. Usually my FOV contains part of the sphere and free space. My question is: how can I calculate the surface area of the sphere...
  41. A

    Electromagnetic Induction and rectangular loop

    the question is that: A rectangular loop with width L and a slide wire with mass m are as shown in Fig. A uniform magnetic field \vec B is directed perpendicular to the plane of the loop into the plane of the figure. The slide wire is given an initial speed of v_0 and then released. There is...
  42. S

    Rectangular scalar components

    Hey, In the question that I'm working on it says to resolve v1 and v2 into rectangular scalar components but i have no idea what a rectangular scalar component is and i can't find it in my textbook. if anyone could tell me what they are that would be very helpful! thanks
  43. S

    Work in rectangular and polar coordinates: result is not the same?

    I'm a little puzzled with the work of a force considering rectangular and polar coordinates. In rectangular coordinates we have: (1) [F]=(Fx [i] + Fy [j]) is the force vector. (2) [dr]=(dx [i] + dy [j]) is small displacement. Then the work is: (3) W = [F] [dr] = (Fx dx + Fy dy) In...
  44. O

    Magnetic field from rectangular current loop

    Another doozie for me. I have been trying this one for 3 days now. I will give my first born for help to this one :uhh: --------------- Calculate the magnitude and direction of the magnetic field produced at point P in Fig. 28.52 by the current I in the rectangular loop. (Point P is at the...
  45. L

    Polar points in rectangular coordinates help

    My teacher has told me I will need to be able to do these in my up and comping exam later this month. He covered the topic a while ago but I didn't quite understand. Here is an example I have. Express the polar point (6, 120 °) in rectangular coordinates. I have no idea how to start doing...
  46. L

    Nu (Nusselt) number for vertical rectangular enclosures

    hi Everyone, I have a couple of books on heat transfer (Heat Transfer, A Practical Approach by Cengel and another one) but none of them contain any information on Nu number for vertical rectangular enclosures. I am trying to find convection coefficient (for free convection) and need Nu to...
  47. S

    How can I simplify the conversion of x^2+y^2-3cos\Theta+4sin\Theta=0 to polar?

    I need to convert x^2+y^2-3cos\Theta+4sin\Theta=0 to polar. Obviously the x^2+y^2 part would = r^2, but how can I get the cos and sin part to simplify?
  48. I

    Rectangular to cylindrical conversion

    Hi =) I was given this problem on a test: a vector A = 2yi - Zj +3xk, was given in rectangular (cartesian) coordinates and I had to convert it to cylindrical coords. What I did to solve it was this: 1) A = 2rsin(theta)i - zj + 3rcos(theta)k 2) partial derivatives a) d/dr =...
  49. E

    Polar to Rectangular conversions

    I am at a standstill with the solution to this problem. I need to convert r^2=2cos(2 theta) to rectangular form. I know that x = rcos(theta) and y = rsin(theta) so far I have r = (2cos(2theta))/r then I substitute for r sqrt(x^2+y^2)= (2cos(2theta))/sqrt(x^2+y^2) Then...
  50. S

    Magnetic field at center of rectangular loop

    Find the magnetic field at the center of a rectangular loop with sides 2a and 2b. well ok due to the sides with length 2a B_{A} = \frac{\mu_{0} i}{2 \pi B} \frac{A}{\sqrt{\frac{A^2}{4} + B^2}} and due to 2B sides B_{B} = \frac{\mu_{0} i}{2 \pi B} \frac{B}{\sqrt{\frac{B^2}{4} +...
Back
Top