Answer:
[tex]\theta = 211.7 degree[/tex]
Explanation:
First displacement of the particle is given as
[tex]r_1[/tex] = 11 m at 82 degree with positive X axis
so we can say
[tex]\vec r_1 = 11 cos82 \hat i + 11 sin82 \hat j[/tex]
[tex]\vec r_1 = 1.53\hat i + 10.9 \hat j[/tex]
resultant displacement of the particle after second displacement is given as
r = 8.7 m at 135 degree with positive X axis
so we can say
[tex]r = 8.7 cos135\hat i + 8.7 sin135\hat j[/tex]
[tex]r = -6.15 \hat i + 6.15 \hat j[/tex]
now we know that
[tex]r = r_1 + r_2[/tex]
now we have
[tex]r_2 = r - r_1[/tex]
so we will have
[tex]r_2 = (-6.15 \hat i + 6.15 \hat j) - (1.53\hat i + 10.9 \hat j)[/tex]
[tex]r_2 = -7.68 \hat i - 4.75 \hat j[/tex]
so angle of the second displacement is given as
[tex]tan\theta = \frac{r_y}{r_x}[/tex]
[tex]tan\theta = \frac{-4.75}{-7.68}[/tex]
[tex]\theta = 211.7 degree[/tex]