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26 articles trouvés pour ce sujet.
A parabolic curve on a bridge 2019-03-09
monica pose la question :
how do i fint the formula for my parabola with the provided information:
the golden gate bridge has a parabola
(343,160) = coordinate
(0,0)= vertex

Penny Nom lui répond.
A semi ellipse 2017-07-25
Ian pose la question :
The arch of the bridge is in the shape of semi ellipse,with its major axis at the water level.suppose the arch is 20ft. High in the middle,and 120 ft. Across its major axis. How high above the water level is the arch,at a point 20 ft.from the center (horizontally). Round of 2 decimal places
Penny Nom lui répond.
A suspension bridge 2016-08-18
sai pose la question :
The main cable of a suspension bridge has the shape of a parabola. The cables are strung from the top of two towers, 61 metres apart, each 15.25 metres high above the roadway. The cable is 1.5 metres above the roadway at the point that is directly between the towers.

where a is the constant and its value to be determined.

a) determine the value of the constant a by using that the fact that height of the suspension cable, h(x) is 15.25 metres at each tower. Hence, write the updated model equation.

Penny Nom lui répond.
Scheduling for a bridge club 2015-09-09
margot pose la question :
Can you help me with scheduling our bridge club?
8 rounds are played with four teams together.
There are 16 teams in total, so our schedule should look like eight 4x4 boxes.
(Each round the four teams play each other over the course of the evening)

Victoria West lui répond.
An isosceles triangle and an arc 2015-02-18
Sreeharsha pose la question :
The diagram shows an isosceles triangle ABC in which BC = AC = 20 cm, and angle BAC = 0.7 radians. DC is an arc of a circle, centre A. Find, correct to 1 decimal place,
(i) the area of the shaded region, [4]
(ii) the perimeter of the shaded region. [4]

Penny Nom lui répond.
A parabolic suspension bridge 2014-03-11
jeffrey pose la question :
the towers of a parabolic suspension bridges 200 meter long are 40 meter high and the lowest point of the cable is 10 meter above the roadway.Find the vertical distance from the roadway to the cable at 50 meter from the center.
Penny Nom lui répond.
A parabolic bridge 2012-12-09
Elizabeth pose la question :
1) The figure below shows a bridge across a river. The arch of the bridge is a parabola and the six vertical cables that help support the road are equally spaced at 4-m intervals. Figure B shows the parabolic arch in an x-y coordinate system, with the left-end of the arch at the origin. As indicated in Figure B, the length of the leftmost cable is 3.072 m.

I'm suppose to find the (x-h)^2=-4a(y-k) equation for this word problem and I really do not know where to begin.

Afterwards, I need to find the lengths of the other cables and the maximum height of the arch of the road as well which I am very confused about

Penny Nom lui répond.
A parabolic bridge 2012-04-24
Adiba pose la question :
A bridge constructed over a bayou has a supporting arch in the shape of a parabola .Find the equation of the parabolic arch if the length of the road over the arch is 100 meters and the maximum height of the arch is 40 meters. I did the problem but not sure is it correct . I did like this f(0)=0we get c=40 if we took quadratic equation in x for a down ward parabola then how to find b and a please show me the answer of either a or b .Or I should use the standard form of parabola y=a(x-h)^2+k then how to find a,h,k please help me
Penny Nom lui répond.
The arc of a bridge 2011-12-05
Marioneta pose la question :
Two same columns placed symmetrically, 40 m apart. The height of columns is 8 m. If the origin of the coordinate system is placed at the foot of the left column the equation of the arc of the bridge: f (x) =-1/80x^2+1/2x+8

What is the maximum height of a boat sailing under the bridge and identify its path.

Penny Nom lui répond.
A suspension bridge 2011-11-30
jennifer pose la question :
suspension bridges like the golden gate bridge, are used to span large distances. when the main curved cables are attached to the deck by vertical cables they will end up in the shape of parabola. assume that we need to build a bridge that spans 2,400 feet. the two towers 165feet tall each where placed at 400feet from either side. the lowest point of the center of the bridge at 10feet. vertical suspension cables where placed at 25foot interval. how many feet of cable are needed to connect the deck to the main cables between the two towers? show all working.
Penny Nom lui répond.
A railway bridge over a road is in the shape of a parabola 2011-11-23
Brennen pose la question :
A railway bridge over a road is in the shape of a parabola, and the bridge is 3 m high in the middle and 6 m wide at its base. A truck that is 2m wide is approaching the bridge. What is the maximum height that the truck can have and still pass under the bridge? Explain.

Thank you!!

Penny Nom lui répond.
The suspension cables of a bridge 2010-07-29
Mike pose la question :
what is the formula for the suspension cables of a bridge. The towers are 200 ft above the roadway The towers are 3400 ft apart The cable if at 8ft in the middle of the span
Robert Dawson lui répond.
The capilano suspension bridge 2010-06-03
nida pose la question :
the capilano suspension bridge in north vancouver is the world's highest footbridge of its kind. the bridge is 140m long . from the ends of the bridge the angles of depression of a point on the river under the bridge are 41 degrees and 48 degrees. how high is the bridge above the river to the nearest metre
Penny Nom lui répond.
A parabolic bridge 2009-10-03
SANDRA pose la question :
a bridge is constructed across the river that is 200 feet wide. the arch is parabolic so that the focus is on the water. A sheep 50 ft wide and 30 ft high passes safely through the arch
a) find equation of the arch
b) find the highest point of the arch

Stephen La Rocque lui répond.
What is so important about quadratics? 2008-11-29
zoe pose la question :
what is so important about quadratics?
Harley Weston lui répond.
A bridge is built in the shape of a parabolic arch 2008-06-02
megan pose la question :
A bridge is built in the shape of a parbolic arch. The bridge has a span of 192 feet and a maximum height of 30 feet. Find the height of the arch at 20 feet from its center. I need the equation and what to fill into the equation...please and thankyou!
Penny Nom lui répond.
Parabolic suspension bridge 2007-10-09
Jessica pose la question :
A suspesion bridge with weight uniformly distributed along its length has twin towers that extend 75 meters abouve the road surfce and are 400 meters apart.The cables are parabolic in shape and are suspended from the tops of the towers. The cables touch the road surface at the center of the bridge. Find the height of the cables at a point 100 meters from the center. (Assume that the road is level.)
Stephen La Rocque lui répond.
The Golden gate bridge 2007-06-17
Khan pose la question :
I am doing a project on parabola and Bridges. I have chosen the Golden gate bridge as my bridge. Now The suspension cables are shaped like a parabola.

We have to derive an equation for this parabola. We have to assume the vertex is (0,0). Now I am having troubles writing the equation in standard form.

The information is this Height of tower above water: 746 ft = 227 m

Height of tower above roadway: 500 ft = 152 m

Length of one side span: 1,125 ft = 343 m

length of suspension span including main span and side spans: 1.2 miles = 6,450 ft

Now my question is this, i KNOW THE standard form for this parabola opening up would be (x-h)squared = 4a (y-k)

Since h,k are 0,0 the equation will now take the form of xsquared = 4ay My question is to find the equation I need to know A how do i get this a based on the above provided info. Thanks for your help and concern.

Penny Nom lui répond.
Can the trailer safely pass under the bridge? 2007-01-02
Jim pose la question :
A truck hauling a double-wide trailer needs to pass under a parabolic-arched bridge en route or take a 50 mile detour. The trailer is 14 feet high and 15 feet wide. The arch supporting the bridge at this underpass is 18 feet high at the center and 40 feet wide at the base. Can the trailer safely pass under the bridge?
Stephen La Rocque lui répond.
A parabolic arch 2006-05-02
Mike pose la question :
A bridge over a river is supported by a parabolic arch...arch is 200 m wide at water level...the maximum height of the arch is 80 m..what is the height of the arch measured from a point on the water 40m from the center of the arch?
Stephen La Rocque lui répond.
The waterway between Lake Huron and Lake Superior 2006-03-21
Trenae pose la question :
the waterway between lake huron and lake superior separates the u.s and canada.it is usually 13 feet above the water when its closed and each section is 210 feet long if the angle of elevation is 70 degrees then what is the distance from the top of the drawbridge to the water and the width of the gap created by the 2 sections of the bridge
Penny Nom lui répond.
12 pairs playing bridge 2001-11-09
Diana pose la question :
I have 12 pairs playing bridge against one another for 12 games. I need to have each pair partnered with another pair -- but only once. I'm looking for a schedule for play for all 12 games. They should only be able to play against another team only once also. (ex: 1/2 v 3/4 then 4/2 v 3/1) Thank you for this opportunity to solve my dilemma.
Claude Tardif lui répond.
A suspension bridge 2001-03-24
Janna pose la question :
The cables of a suspension bridge hang in a curve which approximates a parabola. The road bed passed through the vertex. If the supporting towers are 720m apart and 60m high, find:

a) an equation of the parabola (it's y = 1/2160x2)

b)the height of the cables at a point 30m from the vertex. I substituted 30 in for the x value and got 0.42 and the answer is 42. What did I do wrong?
Denis Hanson and Claude Tardif lui répond.

A bargin with the devil 2001-03-21
DJ pose la question :
There once was a boy who spent all his time dreaming about getting rich. " I would do anything to be rich". The devil, hearing this, appeared before the boy and offered to make him rich. "See that bridge?" said the devil. Just walk across and I will double your money you have now. In fact, each time you cross I will double your money. There is just one thing you must give me $24 after each crossing. The boy agreed. He crossed the bridge, stopped to count his money and, and sure enough, it had doubled. He paid the devil $24 and crossed again. Again his money doubled. He paid another $24 and crossed a third time. Again his money had doubled, but this time there was only $24 left which he had to pay the devil so he was left with nothing. The devil laughed and vanished.
  1. How much money did the boy start with?

Penny Nom lui répond.
Bridges and parabolas 2000-11-18
Lauren pose la question :
My name is Lauren, and Im a secondary school student in Ontario. For my gr11 advanced math class I have to find out how and why parabolics are used in arch bridges and write 3 paragraphs on it. People who cohse satelites and whatnot are lucky - I've found a ton of info, but for arch bridges there seems to be nothing.
Harley Weston lui répond.
Crossing the Bridge 1999-08-27
Debbie Walter pose la question :
If you have four people who need to cross a bridge in the dark with only one flashlight and only two of them can cross at a time and their speeds of crossing are as follows:
  • one person can cross it in one minute
  • one person can cross it in two minutes
  • one person can cross it in five minutes
  • and the slowest person can cross it in ten minutes
what is the shortest amount of time it would take to get all four across the bridge?

Penny Nom lui répond.



Centrale des maths reçoit une aide financière de l’Université de Regina et de The Pacific Institute for the Mathematical Sciences.



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