Question

A body is thrown with a velocity of 9.8 m/s making an angle of ${30}^o$ with the horizontal. It will hit the ground after a time

• A. 1.5 s
• B. 1 s
• C. 3 s
• D. 2 s

Answer 1

Answer: (B)

1 s

Total time of flight of a projectile $=\frac{2u_y}{g}$

where, $u_y$ is the vertical velocity of the projectile $=usin\theta$

Thus, time of flight $=\frac{2usin\theta }{g}$

$=\frac{2\times 9.8\times sin{30}^{\circ }}{9.8}=1s$