Question

Assume that the value for final velocity (Vf) is 20. m/s, acceleration (a) is 5.0 m/s2 and time (t) is 10.0 seconds. Solve for the initial velocity (Vi) using the equation Vf = Vi + at.

Answer 1

V = V0 t + 1/2 a t^2

V0 = (V - a/2 t^2) / t rewriting equation

V0 = (20 - 2.5 * 100) / 10.0

V0 = (20 - 250) / 10 = -23 m/s

Check:

V = -23 * 10 + 5.0 / 2 * 100 = -230 + 250 = 20 final velocity