Answer:
(v-u) = 1.27 m/s
Step-by-step explanation:
Given that,
Mass of a car, m = 1100 kg
Force with which the wall strikes, F = 4000 N
Time, t = 0.35 s
We need to find the change in velocity of the car.
The net force acting on the car is given by :
F = ma
a is acceleration

(v-u) is the change in velocity. Hence, the change in the velocity of the car is 1.27 /s.