Question

A runner slows down after completing works her deceleration is 0.25m/s after 5 sec she is traveling at 4m/s determine her initial velocity

Answer 1

vi = 5.25 m/s

Step-by-step explanation:

We can determine the initial velocity of the runner by using the first equation of motion, as follows:

`v_f = v_i + at\\`

where,

vf = final speed of the runner = 4 m/s

vi = initial speed of the runner = ?

a = deceleration of the runner = - 0.25 m/s²

t = time taken = 5 s

Therefore,

`4\ m/s = v_i + (-0.25\ m/s^2)(5\ s)\\v_i = 4\ m/s + 1.25\ m/s\\`

vi = 5.25 m/s