Recent content by derryck1234

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    Calculating the 'Kicking Out' Force in Toppling Objects

    Answer so far Hi. The body is started by applying a horizontal force at the top until the body's centre of gravity causes it to topple, from this point gravity takes over. My colleague in the office worked on it and made a spreadsheet. We would just like to confirm whether our thinking is...
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    How Is St Venant's Torsion Constant Calculated for Non-Standard Steel Sections?

    Hello I am a Junior Structural engineer and need to know how St Venant's torsion constant is calculated. It appears in structural steel tables, but without knowing how to calculate it, I cannot find its value for non-standard steel sections. Please, can somebody help. Regards Derryck
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    Calculating the 'Kicking Out' Force in Toppling Objects

    Hi. I am trying to calculate the 'kicking out' force created when an object topples over. Attached is a picture of what I mean. The body in the picture topples in a clockwise direction as shown, with its initial pivot point at 'a'. The centre of gravity of the body is shown as cg. Now I have...
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    Is xp(x) in the Range of T for Given Polynomials?

    Homework Statement Let T: P2-P3 be the linear transformation defined by T(p(x)) = xp(x). Which of the following are in R(T)? (a) x2 (b) 0 (c) 1 + x Homework Equations R(T) is the the set of all vectors in P3 which are images under T of vectors in P2. The Attempt at a Solution...
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    Inner product orthogonal vectors

    Homework Statement Let R4 have the Euclidean inner product. Find two unit vectors that are orthogonal to the three vectors u = (2, 1, -4, 0) ; v = (-1, -1, 2, 2) ; w = (3, 2, 5, 4) Homework Equations <u, v> = u1v1 + u2v2 + u3v3 + u4v4 = 0 {orthogonal} The Attempt at a Solution...
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    Inner product generated by matrix

    Homework Statement Find d(u, v), where the inner product is defined by the matrix [1 2] [-1 3] and u = (-1, 2), v = (2, 5) Homework Equations <u, v> = Au . Av d(u, v) = abs(u - v) The Attempt at a Solution I first tried to find the resulting inner product from the...
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    Coordinates relative to a basis

    Homework Statement (In textbook, given a figure, I cannot redraw that figure in this applet, so I shall describe the question in words) I am given a rectangular xy coordinate system determined by the unit basis vectors i and j and an x'y'-coordinate system determined by unit basis...
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    Proving Subspace of Mnn: AB=BA for Fixed nxn Matrix B

    Homework Statement Prove that the set of all n x n matrices A such that AB = BA for a fixed n x n matrix B, is a subspace of Mnn. Homework Equations u + v is in the same vector space as u and v. ku is in the same vector space as u, where k is any real number. The Attempt at a...
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    Is This Set of Triples of Real Numbers a Vector Space?

    Homework Statement Show whether the set is a vector space: The set of all triples of real numbers (x, y, z) with the operations: (x, y, z) + (x', y', z') = (x + x', y + y', z + z') and k(x, y, z) = (kx, y, z) Homework Equations (10 vector space axioms) The Attempt at a Solution...
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    What Are Eigenvalues and Eigenspaces in Linear Transformations?

    Thanks a lot micromass Tell you what if it wasn't for physicsforums I don't know how I would have passed my correspondence linear algebra course... Cheers Derryck
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    What Are Eigenvalues and Eigenspaces in Linear Transformations?

    Ok I think I have solved it: The standard matrix for T is: 0 0 2 0 1 0 1 0 0 1 -2 0 0 0 0 1 Whose characteristic equation is: (lambda - 1)2(lambda + 1)(lambda + 2) = 0 This right? Thanks Derryck
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    What Are Eigenvalues and Eigenspaces in Linear Transformations?

    O ok. So I must turn the resulting matrix into a column vector? I just put them together as matrices...my bad...ok I shall try this agen...shall get back to you to confirm my answer...thanks alot... Ciao...I feel mentally ill that I am such a dumb ***!...but then again...have to learn somehow...
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    What Are Eigenvalues and Eigenspaces in Linear Transformations?

    Ok. So I find the matrix for T to be: 0 1 0 0 0 0 1 0 2 1 0 0 -2 0 0 1 The characteristic equation of which I find to be: (lambda)4 - (lambda)3 - (lambda)2 - (lambda) + 2 Just wondered if there was an easy way to solve this?
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