Kerbox

Hey guys, I could really use some hints on how to solve the integral [math] \int \frac{x}{1+\sqrt{x}} dx [/math] I tried some substitutions, and doing some manipulations on the expression, with no solution. Any help would be much appreciated. Regards, Kerbox

I think Im beginning to get it now. Thanks for your help, I appreciate it

Maybe Im missing some fundemental understanding, but just answer me this: What would the linear and angular acceleration be if the yoyo was in space with only the string tention acting on it, with a constant force F?

But still, in my case, the force would be at just one end. There would be no F2.

Arent you assuming that a force acting tangential to a body has the same effect as the same force acting with a line of action going through the center of mass, as far as linear motion is concerned? Is this a general property when we deal with rigid bodies?

When setting up the equations: G-F_1 = m*a F_2*r = I*alpha we are assuming that F_1=F_2. The basis of my problems with this is that we say that G acts on the yoyo as if it were acting on a pointmass m, at the center of mass. Doesnt the first equation suggest that F does the same thing? But since it acts tangential to the yoyo, something doesnt quite seem right to me. Is it the fact that the linear acceleration HAS to equal the angular acceleration multiplied by the radius that makes the equality F_1=F_2 hold up? EDIT: Yea, I ment alpha, not omega Sorry.

Imagine a jojo. You hold the end firm, and let it go. It falls down, gaining linear speed and angular speed. Forces acting on it is G due to gravity, and F due to the string tension. What I am wondering is this: How do you prove that the F in the equation "F*r = I*\omega" is of the same magnitude as the F in "G-F = m*a"? Since F act normal to the radius, and not through the center of gravity, I dont find it that obvious. Should it be obvious? Thanks