Recent content by smeagol

well I got it from a "physics for scientists and engineers" from tipler. So I figured it would fit better under physics.

Ok, I got that one. Moving on, the next problem is confusing me as well. A baseball bat of length L has a peculiar linear density (mass per unit length) given by \lambda=\lambda_0(1+x^2/L^2) so what I've done is \int_{0}^{L}x\lambda_0(1+x^2/L^2)dx which gives...

so I divide M by 2R\sin{\theta}?

Show that the center of mass of a uniform semicircular disk of radius R is at a point (4/(3*Pi))R from the center of the circle. well I know I am suppose to find this by integration. By this equation M\vec{r_{cm}}=\int\vec{rdm} But, I am not sure how to find dm in this case... do I...

then there's no force pulling on the rope? Also. How is there anywork done on this? the mass is accelerating toward the center, but movint tangent to the circle?

This is something I am learning on my own. However, this problem is confusing me: Red is a girl of mass m who is taking a picnic lunch to her grandmother. She ties a rope of length R to a tree branch over a creek and starts swing from rest at point A, which is a distance R/2 lower than the...