If you know both the acceleration and deceleration of an object, you can find its velocity by considering the time intervals during which each of these forces is acting.
Determine the initial velocity (u) and final velocity (v) of the object.
Calculate the time intervals (t₁ and t₂) during which acceleration and deceleration occur, respectively.
Use the following equations:
a. For acceleration: v = u + at₁
b. For deceleration: v = u + at₂
In both cases, v represents the final velocity, u is the initial velocity, and a is the acceleration or deceleration.
Note: Acceleration and deceleration have opposite signs. If acceleration is positive, deceleration will be negative, and vice versa. The equations above account for this sign difference.
By solving these equations, you can find the final velocity (v) of the object based on its initial velocity (u), acceleration, and deceleration within the given time intervals (t₁ and t₂).