\(\vec{M_0\ }=\vec{r}x\ \vec{f}\)
\(\vec{rA=0i+5j+0k}\) \(\vec{rB=4i+5j-2k}\)
\(F1=-60i+40j+20k\) \(F2=80i+40j-30k\)
\(\vec{rA}\ x\ F1=\frac{\frac{i\ \ j\ \ k}{0\ \ \ 5\ \ \ 0}}{-60\ \ 40\ \ 20}+rB\ x\ F2=\frac{\frac{i\ \ j\ \ k}{4\ \ \ 5\ \ \ -2}}{80\ \ \ 40\ \ -30}\)
\(i\left[\left(5\right)\left(20\right)-\left(0\right)\left(40\right)\right]-j\ \left[\left(20\right)\left(0\right)-\left(0\right)\left(20\right)\right]+k\left[\left(0\right)\left(40\right)-\left(5\right)\left(-60\right)\right]\)
=\(\left(i\ 100,\ j\ 0,\ k\ 300\right)\ \)
\(i\left[\left(40\right)\left(-2\right)-\left(5\right)\left(-30\right)\right]-j\ \left[\left(4\right)\left(-30\right)-\left(80\right)\left(-2\right)\right]+k\ \left[\left(4\right)\left(40\right)-\left(5\right)\left(80\right)\ \right]\ \)
\(=\left(i-30,\ j\ 40,\ k\ -240\right)\ \)
Problema 4
Momento 2d
Para cada figura determine el momento de la fuerza al rededor del punto O.
A)