Answer:
Explanation:
Formula
a = (vf - vi)/t
Givens
a = -2 m/s^2 Note, he is decelerating so the number must indicate he's slowing down. That's why it is minus.
vi = 10 m/s
vf = 0
Solution
-2 m/s^2 = (0 - 10)/t
-2 m/s^2 = -10 / t Multiply both sides by t
-2 m/s^2 * t = - 10 m/s / Divide by - 2
t = -10 / - 2
t = 5 seconds.
