A stone is projected vertically upward from the ground

PHYSICS · Single correct · AP · Physics 1: Algebra-based · Kinematics · Kinematics

Problem

A stone is projected vertically upward from the ground. It eventually falls into a well that is

45\,\text{m}

below the point of projection. If the total time between projection and hitting the water surface is

7\,\text{s}

, neglecting air resistance and taking

g = 9.8\,\text{m s}^{-2}

downward, the initial speed of projection is closest to (a)

34.3\,\text{m s}^{-1}

(b)

27.9\,\text{m s}^{-1}

(c)

19.8\,\text{m s}^{-1}

(d)

28.6\,\text{m s}^{-1}