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Building Collapses
1. B-25 Empire state building crash, 1945 Event July 28, 1945, was a Saturday morning and a ten-ton (having a wingspan of 67 ft 6 in, length of 52 ft 11 in) B-25 bomber en route to Newark airport flew through a dense fog and crashed at an estimated 400 kph into the 79th floor of the Empire State Building, tearing a hole in the 78th and 79th floors and killing ten people in the building. Figure: Impact of B-25 plane Impact To estimate the force applied to the building, we can use; 1. The deceleration of B-25 :- use the force-acceleration method 2. The distance it took the B-25 to come to rest :- use work-energy 3. The time it took the B-25 to come to rest :- use impulse-momentum Plane did not pass through the building, so a distance of 10 to 20 meters for the plane to come to rest could be used for calculations. If the bomber came to rest in 20 meters with a constant deceleration (assumed), the force would be about 4440kN ex