Question

question 40
(problem reference m.4)
a projectile fired from a gun has initial horizontal and vertical components of velocity equal to 40 m/s and 60 m/s, respectively.
what is the acceleration of the projectile when it reaches its maximum height?
4.9 m/s², downward
9.8 m/s², downward
its magnitude is 9.8 m/s², and its direction is changing.
less than 9.8 m/s² and non - zero.
zero m/s²

Explanation:

Step1: Analyze projectile motion

In projectile motion, the only acceleration acting on the projectile is the acceleration due to gravity \(g = 9.8\ m/s^{2}\) (assuming no air - resistance). This acceleration acts vertically downward throughout the motion of the projectile.

Step2: Consider the situation at maximum height

At the maximum height of the projectile, the vertical component of velocity \(v_y = 0\), but the horizontal component of velocity \(v_x\) remains constant (if we neglect air - resistance). However, the acceleration due to gravity still acts on the projectile. The acceleration due to gravity does not depend on the velocity of the object.

Answer:

\(9.8\ m/s^{2}\), downward (the second option)