Quantities that are theoretically zero (assuming ideal conditions):
* Horizontal acceleration (a_x): In an ideal projectile motion scenario, there is no force acting on the projectile in the horizontal direction (ignoring air resistance). Therefore, the horizontal acceleration is zero.
* Vertical force (F_y): The only force acting on the projectile is gravity, which acts vertically downward. However, there is no vertical force acting upwards to counteract gravity. Therefore, the net vertical force is zero at the highest point of the trajectory.
Quantities that are zero at specific points in the trajectory:
* Vertical velocity (v_y) at the highest point: At the peak of its trajectory, the projectile momentarily stops moving upwards before it starts falling back down. At this exact moment, the vertical velocity is zero.
* Vertical displacement (Δy) at the starting and ending points: If the projectile launches and lands at the same vertical height, the total vertical displacement is zero.
Important Considerations:
* Air resistance: In real-world scenarios, air resistance is a significant factor. Air resistance creates a force opposing the motion of the projectile, resulting in a non-zero horizontal acceleration and affecting the trajectory.
* Spin: If a projectile is spinning, it can experience forces due to the Magnus effect, which would make its horizontal acceleration non-zero.
* Non-ideal launching conditions: If the projectile is launched at an angle to the horizontal, the initial vertical velocity is not zero.
In summary, while some quantities like horizontal acceleration and vertical force are theoretically zero in ideal projectile motion, these assumptions often don't hold true in real-world situations.
