Answer:
The value is [tex] a = 4.0 \ m/s^2 [/tex]
Explanation:
From the question we are told that
The velocity is [tex]a = 120 \ km/h = [tex]\frac{120 * 1000}{3600} = 33.3 \ m/s[/tex][/tex]
The time taken is [tex]t = 8.28 \ s[/tex]
The time taken for contact is [tex]t_c = 0.815 \ s[/tex]
The velocity of the of the car after contact is [tex]v_c = 71.0 \ km/h = [tex]\frac{71 *1000}{3600} = 19.7 2 \ m/s[/tex][/tex]
From the equation of kinematics we have that
[tex]v = u + at[/tex]
Here u = 0 \ m/s since the car is initially motionless
=> [tex] 33.3 = 0 + a * 8.28[/tex]
=> [tex] a = 4.0 \ m/s^2 [/tex]
