Recent content by rarkup

Is your co-ordinate system a Cartesian one - ie are the 3 axes at 90 degrees to each other, as in the usual convention of x, y and z axes? The reason I ask is because the subscripts in your question, namely rho and phi, are more commonly used with curvilinear co-ordinate systems (these are...

You might do better if you post your problem as text rather than an attachment - some folks are wary of them.

Would really appreciate some help on this. I'm studying remotely and have no other students to refer to, and the course tutor seems to be on extended leave. I have about 24 hours before the last mail pick-up to make the assignment due date. Any help fully appreciated.

Think of the map with the vectors drawn on as the xy-plane. The z-axis points directly up out of the map, and is positive in the upward direction. North would be directly along the y-axis, and north-east is 45 degrees between the x and y axis. The cross-product either points up out of the map...

Thanks for your response. Rewriting x' in terms of x I get: a_i_j'x_i'x_j' = 1 => a_i_j'l_i_mx_ml_j_nx_n = 1 = a_m_nx_mx_n => a_i_j'l_i_ml_j_n = a_m_n This is close, but it's not clear to me how to shuffle the elements of the rotation matrix L from the LHS to the RHS. I also suspect the...

Homework Statement The equation of a quadric surface takes the form a_i_jx_ix_j = 1, a_i_j = a_j_i relative to the standard coordinate axes. Under a rotation of axes the equation of the surface becomes a'_i_jx'_ix'_j = 1 By considering the coordinates x_i as components of...

Thanks for the welcome and your response tiny-tim. Now it's time to dust off the Algebra books and relearn how to compute components of a vector in the direction of another.

Try using the x2 - y2 = (x + y)(x - y) pattern on the denominator first.

Homework Statement Stress tensor at a point Q in a body has components: pij: | 1 -1 0 | |-1 2 1 | | 0 1 3 | (i) Calculate components of the stress force f across a small area of surface at Q normal to n = (2,1,-1). (ii) The component of f in the direction of n...