Actually the cables of a suspension bridge form a catenary, not a parabola,
but that is another story ...
anyway...
Poor wording in " The
distance between two towers supporting the cable are 800 feet apart
and the height is 200 feet."
should say " The distance between ..... is ... 800 feet ..."
What is 200 feet? Is it the height of the towers or is it the height of the cable
at its lowest point?
There appears to be a piece of data missing.
The suspension bridge cables are in the shape of a parabola. The
distance between two towers supporting the cable are 800 feet apart
and the height is 200 feet. If the vertical support cables are at 100 feet
intervals along the level roadway, what are the lengths of these vertical
cables?
2 answers
I answered this a while back, interpreting that 200 is the height of the towers.
If the vertex is at (0,0) then you have said that y(400)=200
y = ax^2
a(400)^2 = 200
a = 200/160000 = 1/800
y = 1/800 x^2
So now find y at x=100,200,300
The curve is symmetric, so negative values of x produce the same results.
If the vertex is at (0,0) then you have said that y(400)=200
y = ax^2
a(400)^2 = 200
a = 200/160000 = 1/800
y = 1/800 x^2
So now find y at x=100,200,300
The curve is symmetric, so negative values of x produce the same results.
1 answer