A projectile is projected from the origin with a velocity of 30.0 m/s at an angle of 45.0 degrees above the horizontal.What is the velocity and time when the projectile hits the ground?
A) Vx = 21.2 m/s,Vy = -21.2 m/s at t = 4.33 s
B) Vx = 16.7 m/s,Vy = -16.7 m/s at t = 3.33 s
C) Vx = 21.1 m/s,Vy = -16.7 m/s at t = 2.83 s
D) Vx = 16.7 m/s,Vy = -21.2 m/s at t = 4.33 s
E) Vx = 21.2 m/s,Vy = -15.0 m/s at t = 3.33 s

Question

Quizplus · Accepted Answer

The correct answer is A because the projectile's velocity at the highest point is 21.2 m/s at 45 degrees above the horizontal. The time it takes to reach the highest point is 2.16 s. The time it takes to fall from the highest point to the ground is also 2.16 s. So the total time of flight is 4.33 s. The velocity of the projectile when it hits the ground is -21.2 m/s at 45 degrees below the horizontal.

A Projectile Is Projected from the Origin with a Velocity