The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively. If there is no air resistance, how long does it take the football to reach the top of its
Trajectory?
A) 4.0 s
B) 3.0 s
C) 1.0 s
D) 2.0 s
E) 5.0 s

Question

Quizplus · Accepted Answer

The time to reach the top of its trajectory is found using the vertical component of the velocity and the acceleration due to gravity. The formula is $t = \frac{v}{g}$, where $v = 20 \, \text{m/s}$ (the vertical component of the initial velocity) and $g = 9.8 \, \text{m/s}^2$ (the acceleration due to gravity). Plugging in the values, $t = \frac{20}{9.8} \approx 2.0 \, \text{s}$, so the correct answer is D) 2.0 s.

The Horizontal and Vertical Components of the Initial Velocity of a Football