Question

What is the acceleration object velocity of +25m/s to rest in 5.0 s

Answer 1

The average acceleration is -5.0 m·s⁻².

The formula for acceleration (a) is

$a = \frac{v_{f}- v_{i}}{t}$

$v_{f}$ = 25 m·s⁻¹;  $v_{i}$ = 0; $t$ = 5.0 s

∴ $a = \frac{0-25}{5.0}$ = -5.0 m·s⁻²

The negative sign tells you that the object is slowing down, i.e., it is decelerating.