A falling object accerlates from - 10.0m/s to - 30.0m/s how much time does that take

2.04 seconds

Step-by-step explanation:

Falling objects near the surface of the earth have an acceleration of - 9.81 m/s².

Acceleration is the change in velocity over change in time:

a = (v - v₀) / t

-9.81 = (-30.0 - (-10.0)) / t

-9.81 = - 20.0 / t

t = 2.04

It takes 2.04 seconds.