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CRASHING SOFTLY

      
     Consider the pole-vault jumper.  Suppose he falls on a hard floor, you know what will happen?   He falls on a foam bed that cushions and sags as he hit.  On a hard floor, he will experience heavy force all of a sudden.  It will cause him injuries.  On a cushion floor, the time of force acting on him is elongated.  Hence, the average force acting on him per second decreases rapidly.  He can comfortably bear that mild force. 
     To save lives:  "Lengthen the time of force acting on the human body". 

    On a sudden impact, car's air bag is inflated.  It will cushion and save us.  The car's engine, front cover and bumper are in front of us.  On a crash, first they crumble saving our legs. 
        For the same reason, rest rooms are attached at both ends of the train compartment. 
    When the cricket player catches the ball, he lowers his hands to reduce the impact of the force (lengthening time).  He also wears gloves. 
    Those days Apollo rocket crash lands on the sea, to reduce the effecof impact.  Today, rocket land like airplanes. 

    On the moonno waters.  Crash landing is not possible.  Hence, they use small rockets in lunar module; reduce the speed and land it softly. 
    In circus, safety net is used to save from injuries. 
    In the case of airplanes, suppose all the engines fail, it will not fall down.  It will glide like a bird.  Then, the pilots can soft land it on water or land. 
    Parachute experiences high air resistance and slows down the fall of the person. 
    Spread the force over the time to save yourself.    

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