- #1

tukms

- 11

- 0

I have a confusion of a conclusion in the textbook ( I posted it in the attach file )

Net internal torque equals zero ( similarly to conclusion in the Newton’s third law ) but I myself reckon that torque is defined as

$rm{r \times F$

And maybe there occurs the case below :

$rm{F}}_{{\rm{21}}} {\rm{ = - F}}_{{\rm{12} $

But

$rm{r}}_{21} {\rm{F}}_{{\rm{21}}} \ne {\rm{r}}_{12} {\rm{ - F}}_{{\rm{12}$

Could someone help me analyze this situation , I think that the conclusion in textbook is true but it is still fuzzy for me

Thank you in advance

Net internal torque equals zero ( similarly to conclusion in the Newton’s third law ) but I myself reckon that torque is defined as

$rm{r \times F$

And maybe there occurs the case below :

$rm{F}}_{{\rm{21}}} {\rm{ = - F}}_{{\rm{12} $

But

$rm{r}}_{21} {\rm{F}}_{{\rm{21}}} \ne {\rm{r}}_{12} {\rm{ - F}}_{{\rm{12}$

Could someone help me analyze this situation , I think that the conclusion in textbook is true but it is still fuzzy for me

Thank you in advance