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

Respuesta :

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