# If a projectile is shot at an angle of (3pi)/8 and at a velocity of 8 m/s, when will it reach its maximum height?

$t \cong 0 , 41 s$
$t = {v}_{i} \cdot \sin \frac{\alpha}{g}$
$\alpha = 3 \frac{\pi}{18} \cdot \frac{180}{\pi} = {30}^{o} \text{ } \sin 30 = 0 , 5$
$t = \frac{8 \cdot 0 , 5}{9 , 81}$