Question 1013879: The cable of a uniformly loaded suspnsion bridge hangs in the form of parabola.
Vertical wire attachd to the cable supports the 100m long horizontal road.
The longest wire being 30m and shortest wire being 6m.
Find the length of a supporting wire attachd to the road 18m from the middle of the road....
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! The cable of a uniformly loaded suspension bridge hangs in the form of parabola.
Vertical wire attached to the cable supports the 100m long horizontal road.
The longest wire being 30m and shortest wire being 6m.
Find the length of a supporting wire attached to the road 18m from the middle of the road.
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Use the road as the x-axis.
Find the equation of the parabola.
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The longest wires attach to the cable at (-50,30) and (50,30)
The shortest wire attaches at (0,6)
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The equation is of the form y = ax^2 + c
6 = c (from point (0,6))
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30 = a*50^2 + 6
a = 24/2500 = 6/625
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f(x) = 6x^2/625 + 6 is the eqn of the parabola.
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Find the length of a supporting wire attached to the road 18m from the middle of the road.
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f(18) = 6*324/625 + 6
= 9.1104 m
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