A projectile is launched in the air with an initial velocity of 40 m/sec from a height of 1.2 meters. Which of the following equations represents the projectiles height, h, in meters, over time, t, in seconds?

A. h=-40t^2+1.2

B. h=-16t^2+40t+1.2

C. h = - 4.9t^2+1.2

D. h = - 4.9t^2+40t+1.2

For this case, the first thing that should be taken into account is the following kinematics equation in its generic form:

h = a * (1/2) * t ^ 2 + vo * t + h0

Where,

a: acceleration

vo: initial speed

h0: initial height.

t : time

h: final height

Substituting the values:

h = - 4.9 t ^ 2 + 40t + 1.2

Note:

g = 9.8 m / s

Answer:

D h = - 4.9 t ^ 2 + 40t + 1.2