A drawbridge is I = 180 feet long when stretched across a river. As shown in the
ID: 3024594 • Letter: A
Question
A drawbridge is I = 180 feet long when stretched across a river. As shown in the figure below, the two sections of the bridge can be rotated upward through an angle of a = 30 degree drawbridge If the water level is 35 feet below the closed bridge, find the distance d between the end of a section and the water level when the bridge is fully open. (Round your answer to one Place.) Approximately how far apart are the ends of the two sections when the bridge is fully opened, as shown in the figure? () Find the total length of the slide to the nearest foot, if alpha = 24, beta = 35 degree, a = 15 n, and b = 160 ft.Explanation / Answer
tan alpha=opposite/adjacent
opposite=d and adjacent=l/2=90
tan 30=adjacent/90
adjacent=90 tan 30
adjacent=52 feet
d=adjacent+35=87 feet
b. cos 30=hypotenuse/base
cos 30=hypotenuse/90
hypotenuse=90 cos 30=77.94 feet
Therefore the total length of bridge=2*77.94=155.9 feet