air bags. suppose you want to design an air bag system that can protcet the driver in the head- collision at a speed of 100 km/h (60 m/hr) Estimate how fast the driver bag must inflate to effectively protect the driver. how does the use of a seat belt help the driver.
PLEASE EXPLAIN IT.
2007-02-01 18:43:32 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
preeeeeeety fast... they all inflate at .02 sec...
2007-02-01 18:47:32 · answer #1 · answered by doctorhector 3 · 0⤊ 0⤋
You want the bag to reach the driver before the driver reaches the windshield or dashboard. Estimate the distance the driver's head would move, say about 1 meter. Assume the worst case that the car stops instantly on collision. The driver's head will then be moving forward at 100 km/hr or about 28 m/sec. So the air bag must deploy faster than 1/28 sec For safety you would probably want the airbag to contact the driver in about half that time, or about 1/50 sec.
Without a seat belt, the driver's head and body would move straight ahead at full velocity. With a seat belt (no shoulder harness), the body will rotate instead, and the forward velocity of the head will be decreased and he will contact the air bag sooner.
2007-02-02 02:57:14 · answer #2 · answered by gp4rts 7 · 0⤊ 0⤋
Well, I think it has to do with the length the car travels after the impact. Estimate that the length from the front of the car to the passenger seat is 2 meters.
Then, the time that needs to be employed must be smaller than the speed the car is travelling.
=>
note*
1000 meter = 1 km
3600 seconds = 1 hour
2 meters/t > 100,000 meters/3600 sec
t < 0.072 seconds
The seat belt increases the length that is travelled after impact, so for example instead of 2 meters, it becomes 2.5 meters.
2007-02-02 02:58:04 · answer #3 · answered by tedhyu 5 · 0⤊ 0⤋
Check out the motor vehicle safety standard .org or .gov as all this has been figured out already
2007-02-02 02:53:28 · answer #4 · answered by Anonymous · 0⤊ 0⤋