Question

A brick is released with no initial speed from the roof of a building and strikes the ground in 1.80 s , encountering no appreciable air drag. how tall, in meters, is the building?

Answer 1

Kinematics is used in this problem. The mass does not matter here because the question is mass independent. vi = 0 vf = x d = ? d = vi + 1/2 a t^2 d = 0 + 1/2 (9.8) (1.8)^2 d = 15.9 m (counting sig figs)