An object with a mass of 100 g is in free fall. What is the speed of the object after it has fallen for 4 seconds?

A. 39 m/s

B. 9.8 m/s

C. 25 m/s

D. 96 m/s

A = 9.81 m/s² for any object in free fall.

Assume object started with speed v₀ = 0

Kinematic equation, with a = 9.81 m/s² and t = 4s

v = v₀ + at

v = at

v = (9.81 m/s²) (4 s)

v = 39 m/s

The speed of object is

39 m/s after 4 seconds of free fall