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WHEN THE CAR'S AIR-BAG WILL DEFLATE ?

 


     We assume that we know everything about the elementary concept "acceleration".  But there is more to know.

     Definition:  Whenever a body undergoes change in speed or change in direction, it said to be "accelerating".


     We know, if any body falls freely, its speed will increase by 9.8m/s^2 for every second due to earth's gravity and it is denoted by the symbol 'g'.  Also, we can say, if a body experiences 9.8 m/sˆ2 acceleration, it is acted upon by 'one g' force.




     If you plop down on a chair, you will experience up to 10 g force for a brief time.

     Even your sneeze will put you in a '2.5g' force.  In a thrill ride of roller coaster, we experience 'high g' for a very brief time.  There are 'human centrifuge' which creates 'high g' by spinning fast. pilots and astronauts are trained to experience 'high g' in these centrifuges.

     When a car crashes, it suddenly decelerates (negative acceleration).  The airbag in front of all the seats will be inflated only if the acceleration exceeds '60g'.  Prince Diana's car crash produced  '70-100g' force.  A word of caution.  If you experience a force of 4g-6g for a long time, you will be "blacked out".  Our body has many organs with different densities and masses.  Hence each will get its own g - force.


     Feather or boulder; earth always gives 'one g' force to everything.  It is because gravitational force proportionally increases with the mass [g = force/mass ].




     In pole-vault jump, the person falls on the cushion, to reduce g- force. In a car, the engine is mounted on front and luggage is kept on the back to reduce the effect of g-force in an impact. 

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