Recent content by derryck1234

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...

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

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...

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...

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...

Thanks.

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...

Thanks

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...

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...

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...

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

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

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 a lot... Ciao...I feel mentally ill that I am such a dumb ***!...but then again...have to learn somehow...

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?