Recent content by alcoholicsephiroth

This is essentially a "homework question", but I'm not looking for an explicit solution so I have posted it here. 1. Homework Statement Find a simplified expression for the Riemann tensor in terms of the connection in normal coordinates. 2. Homework Equations Riemann tensor =...

Ahh that follows, so only the component perpendicular to the radius is rw. (Why don't lecturers say these things?!) Anyway I'll go and look over it, and hopefully I won't be adding anything to this thread :cool: Many thanks!

Thank you for the replies. I haven't been available since posting but I'm around now. http://www.geocities.com/alcoholicsephiroth/ellipticalorbit.JPG I understand that for a circular orbit the tangential and radial velocity are perpendicular, (and for this case radial velocity = 0), and...

Ok so the total energy of a body following a given trajectory around a much larger body (eg. Earth and sun), is described by : E(total) = (1/2)mv^2 + U (where U = grav. potential energy) E(total) = (1/2)mv^2 - (GMm)/r (1/2)mv^2 can then be expanded to give : E(total)...

Wow I see the light (I think) :P I'll just take a quick guess here, and say that a small addition to your answer to my second question would be 'only if your element is a point mass, or the element has moment of inertia = dm(r^2) ' ? I think this follows, looking at the working for a...

But what of the general definition of moment of inertia ? I = sum of mr^2 for each particle in the solid. Does it not follow from this definition that the moment of inertia of any continuous solid can be found by turning the above sum into an integral, without the need to consider...

Thanks for the link, although I don't actually have any problems with that derivation. What I don't understand is the why my own approach [just integrating (y^2)(dm) to obtain I ] and the derivation shown in the link [ starting with dI = (1/2)(y^2)(dm) ] are any different. When finding I...

Posted this question in the calculus section but I guess it's more of a basic physics question, so I've copied it here - Taking a uniform solid sphere of radius R and mass M, with the centre of mass at the origin, I divided it into infinitesimal disks of thickness dx, and radius y. I need to...

This is not a homework question but I figured this was the most appropriate place to post it- Taking a uniform solid sphere of radius R and mass M, with the centre of mass at the origin, I divided it into infinitesimal disks of thickness dx, and radius y. I need to find the moment of inertia...