2. An inflatable bag is located in the dashboard of a car. Inacollision, the bag expands suddenly and cushions the impact ofthepassenger. The forward motion of the passenger must be stoppedinabout 30 cm of motion if contact with the hard surfaces of thecaris to be avoided.
a) For a 70-kg person with a 30-cm allowed stopping distance,showthat the magnitude of the average force is given by thefollowingexpression: F = 117 Vo^2, newtons.
Notice that the necessary stopping force increases as the squareofthe velocity of the automobile (and the passenger).
b) Assume that Vo = 70 km/h and find F.
c) If the force that you evaluated in part b) isuniformlydistributed over a 1000-cm^2 area of the passenger's body,find theapplied force per square meter. The estimated strength ofbodytissue is 500,000 Pa. NOTE: One Pa (Pascal) is a force of 1Ndivided by one area of 1 square meter.
d) Kindly, repeat the calculation of part c) with v = 100 km/h.Itis safe to say that the force per unit area just calculatedwouldprobably injure the passenger?
2. An inflatable bag is located in the dashboard of a car. Inacollision, the bag expands suddenly and cushions the impact ofthepassenger. The forward motion of the passenger must be stoppedinabout 30 cm of motion if contact with the hard surfaces of thecaris to be avoided.
a) For a 70-kg person with a 30-cm allowed stopping distance,showthat the magnitude of the average force is given by thefollowingexpression: F = 117 Vo^2, newtons.
Notice that the necessary stopping force increases as the squareofthe velocity of the automobile (and the passenger).
b) Assume that Vo = 70 km/h and find F.
c) If the force that you evaluated in part b) isuniformlydistributed over a 1000-cm^2 area of the passenger's body,find theapplied force per square meter. The estimated strength ofbodytissue is 500,000 Pa. NOTE: One Pa (Pascal) is a force of 1Ndivided by one area of 1 square meter.
d) Kindly, repeat the calculation of part c) with v = 100 km/h.Itis safe to say that the force per unit area just calculatedwouldprobably injure the passenger?
