A suspension bridge is to be built across a valley where it is known that the wind can gust at 5 s intervals. It is estimated that the speed of transverse waves along the span of the bridge would be 400 ms-1. The danger of resonant motions in the bridge at its fundamental frequency would be greatest if the span of the length of ...
A. 2000 m
B. 1000 m
C. 400 m
D. 80 m
E. 40 m
