Question

( begin{aligned} &=frac{left|vec{r}_{1}-r_{2}right|}{sqrt{left(vec{r}_{1}-vec{r}_{2}right) cdotleft(vec{r}_{1}-vec{r}_{2}right)}} &=frac{sqrt{3^{2}+4^{2}-2 vec{r}_{1} overrightarrow{r_{2}}}}{sqrt{25-2 times 3 times 4 times cos 60}} =& sqrt{13} end{aligned} )

# In a two dimensional motion of a particle, the particle moves from point A, position vector 1, to point B position vector rą. If the magnitude of these vector are respectively r1 = 3 and 12 = 4 and the angle they make with the x-axis are 0, = 75°, O2 = 15° respectively, then magnitude of the displacement vector is- (A) 13 (B) /13 (©) V5 (D) VI

Solution