Answer:
7.5s
Explanation:
Given parameters:
Velocity = 30m/s
Deceleration = 4m/s²
Unknown:
Time it takes for the car to come to complete rest = ?
Solution:
To solve this problem, we use the kinematics expression below:
v = u + at
Since this is a deceleration
v = u - at
v is the final velocity
u is the initial velocity
a is the acceleration
t is the time taken
v - u = -at
0 - 30 = -4 x t
-30 = -4t
t = 7.5s
