Question

part a. A delivery drone, hovering at an altitude of 260. m above the ground, drops a package. ("dropped" means that it was stationary when released ). How long will it take to reach the ground? part b. What will be the velocity of the package the instant before it hits the ground?

Answer 1

Given:

h= 260m (height)

a = 9.8 m/s^2 (acceleration due to gravity )

Apply:

• a)

h = 1/2 a t^2

Replacing:

260 = 1/2 (9.8) t^2

260 / (1/2 * 9.8 ) = t^2

t = √[260 / (1/2 * 9.8 ) ]

t = 7.28 s

• b)

Apply.:

Vf = vi + at

Vf = finale velocity

Vi = initial velocity ( rest ) = 0 m/s

Vf = -9.8 (7.28 ) = -71.34 m/s