It is told that during World War II the Russians, lacking sufficient parachutes for airborne operations, occasionallydropped soldiers inside bales of hay onto snow.The human body can survive an average pressure on impact of 30 lb/in?. Suppose that the lead plane drops adummy bale equal in weight to a loaded one from an altitude of 100 ft, and that the pilot observes that it sinksabout 2 ft into the snow. If the weight of an average soldier is 180 lb and his effective area is 5 ft’, is it safe todrop the men?Hints: there two ways to approach this problem :The easier way. Apply the Law of Conservation of Energy (Mechanical Energy is not conserved)A little more complicated : Use Work-Energy theorem to find the total average force acting onsoldier while moving in the snow.Remember: Just before reaching the snow Mechanical Energy is conserved .You are asked to find the force of the snow. The net average force on the soldier is upward and :F=Fsmnow- Mg.

Given data:Average Pressure a human body can survive = 30 lb/in2 = 4320 lb/ft2Dummy Bale has 180 lb…

It is told that during World War II the Russians, lacking sufficient parachutes for airborne operations, occasionally dropped soldiers inside bales of hay onto snow. The human body can survive an average pressure on impact of 30 lb/in?. Suppose that the lead plane drops a dummy bale equal in weight to a loaded one from an altitude of 100 ft, and that the pilot observes that it sinks about 2 ft into the snow. If the weight of an average soldier is 180 lb and his effective area is 5 ft², is it safe to drop the men?

It is told that during World War II the Russians, lacking sufficient parachutes for airborne operations, occasionally dropped soldiers inside bales of hay onto snow. The human body can survive an average pressure on impact of 30 lb/in?. Suppose that the lead plane drops a dummy bale equal in weight to a loaded one from an altitude of 100 ft, and that the pilot observes that it sinks about 2 ft into the snow. If the weight of an average soldier is 180 lb and his effective area is 5 ft², is it safe to drop the men?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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