Question

The human body can survive a negative sudden stop if the magnitude of the acceleration is less than 250m/s2. If you are in an automobile accident with an initial speed of 105km/h and are stopped by an airbag that inflates from the dashboard, over what distance must the airbag stop you for you to survive the crash?

Answer 1

$$v^2=v_0^2+2ad,$$ $$0=v_0^2+2ad,$$ $$d=\dfrac{-v_0^2}{2a},$$ $$d=\dfrac{-(29.16\ \dfrac{m}{s})^2}{2\cdot(-250\ \dfrac{m}{s^2})}=1.7\ m.$$