Answer:
The correct answer is - 4 m/s
Step-by-step explanation:
Given:
time = 20 sec
velocity= 80 m/s
Accelaration = ?
Solution:
formula for the accelaration can be drive from the for
vi = vf + ( a.t)
0 m/s (rest) = 80 m/s + (a.20s.-1)
a.20.-1= -80,
we check if this is true;
0 m/s= 80 + -80 = 0 so its true.
so a.20.-1= -80,
a= 80/20 ,
Thus, the correct answers a = 4 m/s