Official Correct Choice:
Option B: \( v_y = 0 \, , \, v_x = \text{constant} \)
Concept:Projectile motion combines uniform horizontal motion and uniformly accelerated vertical motion due to gravity.
Solution:- Throughout the entire flight, the horizontal velocity \( v_x \) remains constant because there is no horizontal force (ignoring air resistance).
- The vertical velocity \( v_y \) decreases as the object rises, reaching exactly zero at the absolute highest point of the trajectory, before becoming negative as it falls back down.
- Therefore, at the peak, \( v_y = 0 \) and \( v_x = \text{constant} \).
Why other options are incorrect:If \( v_x \) was also zero (Option A), the projectile would drop straight down like a stone. Gravity ensures \( v_y \) is never constant (Option C, D).
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