Recent content by RIgel

GreetingsTo be straight, I've been studying Goldstein Classic mechanics.While studying, it turned out that this is not a book for my level,(knew it would be challenging, but even far beyond)but even after finding out that something is wrong, i kept studying this book, by doing some research or...

Yep thanks thanks ( ´∀｀) I think i got it \frac{d}{dt}(\frac{∂r_i}{∂q_j})=(\frac{∂\dot{r_i}}{∂q_j}) problem is perfectly settled Gosh i can't believe why I was wandering, you really woke me up And it indeed is a mistake to write those vectors as normal font, but making math symbols neat as...

Well it seems, because time derived term is on denominator, so if i think 'dt' included in \partial{\dot{p}} as if it is on the numerator of \frac{d}{dt}(\frac{\partial{U}}{ \partial{ \dot{q}}} )⋅δq (then it would be like (\frac{d}{dt}(\partial{U}\frac{1}{∂}(\frac{dt}{q}))⋅δq), than it...

currently working on format.. sor i was not preparedHi I think this question would be much related to calculus more than physics cause it seems I'd lost my way cause of calculus... but anyway! it says, Q=- \frac{\partial{U}}{\partial{q}}+\frac{d}{dt}(\frac{\partial{U}}{ \partial{ \dot{q}}} )...