Projectile motion Knowledge-Based Practice

Questions

1. 1.

   An ideal projectile is launched from level ground at an angle of 45° above the horizontal with a total time of flight of 6.0 s. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s$^2$, what is the horizontal range of the projectile?

   • A) 90 m
   • B) 120 m
   • C) 150 m
   • D) 180 m
2. 2.

   An ideal projectile launched from flat ground reaches a maximum height $H$ and achieves a total horizontal range $R$. If the horizontal range is equal to four times the maximum height ($R = 4H$), what is the launch angle of the projectile above the horizontal?

   • A) $45^\circ$
   • B) $30^\circ$
   • C) $60^\circ$
   • D) $76^\circ$
3. 3.

   Two seconds after being launched from level ground, a projectile is moving horizontally at a speed of 15 m/s. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s$^2$, what was the launch speed of the projectile?

   • A) 15 m/s
   • B) 20 m/s
   • C) 35 m/s
   • D) 25 m/s
4. 4.

   Two projectiles are launched from level ground with the same initial speed at angles of 30° and 60° above the horizontal, respectively. Neglecting air resistance, what is the ratio of the maximum height reached by the first projectile to that reached by the second projectile?

   • A) 1/9
   • B) 1/3
   • C) 1/2
   • D) $1/\sqrt{3}$
5. 5.

   A projectile launched from level ground reaches a maximum height of 45 m. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s$^2$, what is the total time of flight of the projectile before it strikes the ground?

   • A) 6.0 s
   • B) 3.0 s
   • C) 4.5 s
   • D) 9.0 s
6. 6.

   A stone is thrown horizontally from the edge of a tall cliff with an initial speed of 15 m/s. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s$^2$, what is the speed of the stone 2.0 s after release?

   • A) 25 m/s
   • B) 20 m/s
   • C) 35 m/s
   • D) 15 m/s
7. 7.

   An object is launched from level ground into projectile motion under the influence of gravity alone. If the speed of the object at the highest point of its trajectory is exactly half of its initial launch speed, what is the launch angle above the horizontal?

   • A) 30°
   • B) 45°
   • C) 60°
   • D) 75°
8. 8.

   A projectile is launched from flat ground with an initial speed of 50 m/s at an angle of 37° above the horizontal. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s², what is the total horizontal range achieved by the projectile? (Take sin 37° = 0.6 and cos 37° = 0.8.)

   • A) 120 m
   • B) 180 m
   • C) 240 m
   • D) 300 m
9. 9.

   A projectile is launched from flat ground with an initial speed of 60 m/s at an angle of 30° above the horizontal. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s$^2$, what is the maximum height reached by the projectile above the ground?

   • A) 45 m
   • B) 60 m
   • C) 90 m
   • D) 180 m
10. 10.

    A ball is launched horizontally from the edge of a 45 m high cliff with an initial speed of 20 m/s. Neglecting air resistance and taking the acceleration due to gravity as 10 m/s2, what is the horizontal distance travelled by the ball before it strikes the ground?

    • A) 45 m
    • B) 60 m
    • C) 90 m
    • D) 120 m

Answers and step-by-step solutions appear after you finish the test.