Answer:
14.7 m/s
Step-by-step explanation:
During a crash, a car moving with some initial velocity comes to rest. This means the car undergoes a constant deceleration. So according to the question, we have
Given:
- v = final velocity of the car = 0 m/s
- a = acceleration of the car =
![-50g = -50* 9.8\ m/s^2 = -490\ m/s^2](https://img.qammunity.org/2020/formulas/physics/college/9sxdt8cg3r991u4vlxn92x8ocv2rwob98z.png)
- t = time for which the crash occurs = 30 ms = 0.03 s
Let us assume that the maximum initial velocity of the car for which the driver still could survive on a crash be u.
During the crash, the car moves with a constant acceleration. so using the equation for a constant acceleration, we have
![v = u+at\\\Rightarrow u = v-at\\\Rightarrow u = 0-(-490)(0.03)\\\Rightarrow u =14.7](https://img.qammunity.org/2020/formulas/physics/college/je7d10mk41jka4v8bl07lqfg51vccrbvqk.png)
Hence, the highest speed that the car could have had such that the driver survived is 14.7 m/s.