Question

An initially motionless test car is accelerated uniformly to 120 km/h in 8.28 s before striking a simulated deer. The car is in contact with the faux fawn for 0.815 s, after which the car is measured to be traveling at 71.0 km/h. What is the magnitude of the acceleration of the car before the collision

Answer 1

The value is
`a =  4.0 \ m/s^2`

Step-by-step explanation:

From the question we are told that

The velocity is
`a =  120 \  km/h =  [tex](120 *  1000)/(3600) =  33.3 \  m/s`[/tex]

The time taken is
`t  =  8.28 \  s`

The time taken for contact is
`t_c  =  0.815 \  s`

The velocity of the of the car after contact is
`v_c =  71.0 \  km/h = [tex](71 *1000)/(3600) =  19.7 2 \  m/s`[/tex]

From the equation of kinematics we have that

`v =  u  + at`

Here u = 0 \ m/s since the car is initially motionless

=>
`33.3 =  0  + a *  8.28`

=>
`a =  4.0 \ m/s^2`