# A projectile is shot from the ground at a velocity of 7 m/s at an angle of (5pi)/12. How long will it take for the projectile to land?

Mar 12, 2016

$\approx 1.38 s$

#### Explanation:

velocity of projection$u = 7 m {s}^{-} 1$
angle of projection,$\alpha = 5 \frac{\pi}{12}$
If time of flight be T s
then
$0 = u \sin \alpha \times T - \frac{1}{2} \times g \times {T}^{2}$

$\implies T = \frac{2 u \sin \alpha}{g} = \left(2 \times 7 \times \sin \frac{5 \frac{\pi}{12}}{9.8}\right) \approx 1.38 s$