A projectile is fired horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its displacement 3.0 s after it is fired? horizontal vertical
A)44 m -29 m
B)170 m zero m
C)170 m -44 m
D)210 m -44 m
E)210 m zero m

Question

Quizplus · Accepted Answer

The horizontal component of displacement is given by:

distance = speed x time = 57 m/s x 3.0 s = 170 m (since there is no acceleration in the horizontal direction)

The vertical component of displacement is given by:

distance = initial velocity x time + 0.5 x acceleration x time^2

where the initial velocity is zero (since the projectile is fired horizontally) and the acceleration is -9.8 m/s^2 (since the projectile is subject to gravity).

distance = 0 x 3.0 s + 0.5 x (-9.8 m/s^2) x (3.0 s)^2 = -44.1 m (the negative sign indicates the displacement is in the downward direction)

Therefore, the answer is C: 170 m horizontal displacement and -44 m vertical displacement.

A Projectile Is Fired Horizontally with an Initial Speed of 57