Question

As a projectile moves through its parabolic trajectory, which of the following quantities remains constant (Select all that apply.)?

A) Vertical acceleration
B) Horizontal acceleration
C) Horizontal velocity
D) Vertical velocity

Answer 1

In projectile motion, the vertical acceleration due to gravity remains constant, as does the horizontal velocity because there is no horizontal acceleration. Vertical velocity, however, changes throughout the projectile’s flight.

Step-by-step explanation:

As a projectile moves through its parabolic trajectory, the following quantities remain constant:

A) Vertical acceleration: The acceleration due to gravity is constant in the vertical direction and is the same for all objects in projectile motion, assuming there is no air resistance.

C) Horizontal velocity: In the absence of air resistance, the horizontal velocity remains constant because there is no horizontal acceleration (the horizontal acceleration is zero).

The quantities that do not remain constant are:

B) Horizontal acceleration: As mentioned, this is actually zero and thus does not change, but it is not 'constant' in the sense that it contributes to the motion.

D) Vertical velocity: This changes throughout the motion, becoming zero at the peak and increasing in magnitude as the projectile falls back to the ground, in the opposite direction of the initial vertical velocity.

Vertical acceleration remains constant due to gravity, and horizontal velocity remains constant due to the lack of horizontal forces acting on the projectile (neglecting air resistance).