Homework Statement
How did this approximation come about? It doesn't seem like it's by L'Hopital's rule. Thanks!
Homework Equations
The Attempt at a Solution
I simply don't understand this conversion. I've only worked with du, dx, dy, etc. before. How do you change a d(γmu) into some kind of du?
(This is in the contest of relativity, although this info is not essential i think)
Thanks! :)
Then there is no angular momentum and only linear momentum?
EDIT: actually i made an error with my question. the new image is attached.
If ri` and ai` are parallel, shouldn't the cross-product be 0? So in the last line, the Ʃ miri` × A would be left instead?
Background: we're trying to show that the rate of change of angular momentum of an object about its center of mass (position given by R) is equal to the total torque about R.
Why are the terms in red equal to 0? If anything, shouldn't the terms circled in in blue be equal to zero since the...
We have the representation of torque attached. The components of r are (x,y,z).
Where did the matrix come from and how did we get the stuff in the matrix? (Basically I understand all the steps except the step from the 3rd line to the 4th line.)
Thank you very much!