A driver of mass 80kg collides head-on against a huge brick wall. During the crash, the driver hits his face against the steering wheel and experts determine that his deceleration on impact was about 250m/s^2.
1) Estimate the force he sustains on impact.
2) If the car had an initial velocity of 22m/s, estimate the driver's time of impact with the steering wheel.
3) The driver suffers huge facial injuries. From a physicist's point of view, how could the use of an airbag help reduce such injuries?
2007-03-01 04:22:36 · 3 answers · asked by gianluca_azz 1 in Science & Mathematics ➔ Physics
What a depressing question, the dude is dead! Can't they work in like a crash-test dummy into the question and not have such a morbid question?
2007-03-01 04:27:23 · answer #1 · answered by Anonymous · 0⤊ 0⤋
1) Newton's 1st law of motion in the form F = ma gives you the force = 80kg x 250m/s^2 = 20 000 Newton = 10^4 N
2) You have to "estimate" , thus choose the distance between the driver and the steering-wheel as, say, 0,5 m. Then use s = v initial x t - 1/2 a t^2 where a = 250 ms^2 (negative because it's a "deceleration"). From this quadratic equation determine the time which will be the positive root.
3) The airbag would have absorbed a great deal of the collision energy
2007-03-01 04:38:13 · answer #2 · answered by physicist 4 · 0⤊ 0⤋
F=MA
F= 80 * 250
2- Just use one of the kinematic equations...u know acceleration. VI, VF
3- I think it would lengthen the time he was incontact withit so the F would be more gradual or something like that. Plus the airbag is more elastic and has more "give" than the wheel
hope this helps
2007-03-01 04:31:39 · answer #3 · answered by mmmmmmm 3 · 0⤊ 0⤋