Tamil Nadu Board of Secondary EducationHSC Arts Class 12

A bridge has a parabolic arch that is 10 m high in the centre and 30 m wide at the bottom. Find the height of the arch 6m from the centre, on either sides - Mathematics

Advertisements
Advertisements
Sum

A bridge has a parabolic arch that is 10 m high in the centre and 30 m wide at the bottom. Find the height of the arch 6m from the centre, on either sides

Advertisements

Solution


PQ = 2a = 30 m

a = 15 m

Point Q be (15 , –10)

Equation of the parabola

x2 = – 4 ay  .......(1)

Q lies on parabola

152 = – 4a( –10)

a = `225/40`

(1) ⇒ x2 = `- 4(225/40)y`

x2 = `225/10 y`

Let B(6, y) lies on parabola

62 = `225/10 y_1`

y1 = `- (36 xx 10)225`

= `(- 8)5`

= `8/5 "m"`

AB = AC – BC

= `10 - 8/5`

= `(50 - 8)/5`

= `42/5`

AB = 8.4 m

∴ The height of the arch 6 m from the centre is 8.4 m

Concept: Real Life Applications of Conics
  Is there an error in this question or solution?
Chapter 5: Two Dimensional Analytical Geometry-II - Exercise 5.5 [Page 214]

APPEARS IN

Tamil Nadu Board Samacheer Kalvi Class 12th Mathematics Volume 1 and 2 Answers Guide
Chapter 5 Two Dimensional Analytical Geometry-II
Exercise 5.5 | Q 1 | Page 214

RELATED QUESTIONS

A tunnel through a mountain for a four-lane highway is to have a elliptical opening. The total width of the highway (not the opening) is to be 16 m, and the height at the edge of the road must be sufficient for a truck 4 m high to clear if the highest point of the opening is to be 5 m approximately. How wide must the opening be?


At a water fountain, water attains a maximum height of 4 m at horizontal distance of 0.5 m from its origin. If the path of water is a parabola, find the height of water at a horizontal distance of 0.75 m from the point of origin.


An engineer designs a satellite dish with a parabolic cross-section. The dish is  5m wide at the opening, and the focus is placed 1 2. m from the vertex. Position a coordinate system with the origin at the vertex and the x-axis on the parabola’s axis of symmetry and find an equation of the parabola


An engineer designs a satellite dish with a parabolic cross-section. The dish is 5 m wide at the opening and the focus is placed 1.2 m from the vertex. Find the depth of the satellite dish at the vertex


Parabolic cable of a 60 m portion of the roadbed of a suspension bridge are positioned as shown below. Vertical Cables are to be spaced every 6m along this portion of the roadbed. Calculate the lengths of first two of these vertical cables from the vertex.


Cross-section of a Nuclear cooling tower is in the shape of a hyperbola with equation `x^2/30^2 - y^2/44^2` = 1. The tower is 150 m tall and the distance from the top of the tower to the centre of the hyperbola is half the distance from the base of the tower to the centre of the hyperbola. Find the diameter of the top and base of the tower


A rod of length 1 2. m moves with its ends always touching the coordinate axes. The locus of a point P on the rod, which is 0 3. m from the end in contact with x-axis is an ellipse. Find the eccentricity


Assume that water issuing from the end of a horizontal pipe, 7 5. m above the ground, describes a parabolic path. The vertex of the parabolic path is at the end of the pipe. At a position 2 5. m below the line of the pipe, the flow of water has curved outward 3 m beyond the vertical line through the end of the pipe. How far beyond this vertical line will the water strike the ground?


On lighting a rocket cracker it gets projected in a parabolic path and reaches a maximum height of 4 m when it is 6m away from the point of projection. Finally it reaches the ground 12 m away from the starting point. Find the angle of projection


Points A and B are 10 km apart and it is determined from the sound of an explosion heard at those points at different times that the location of the explosion is 6 km closer to A than B. Show that the location of the explosion is restricted to a particular curve and find an equation of it.


Choose the correct alternative:

An ellipse has OB as semi-minor axes, F and F’ its foci and the angle FBF’ is a right angle. Then the eccentricity of the ellipse is


Choose the correct alternative:

The eccentricity of the ellipse (x – 3)2 + (y – 4)2 = `y^2/9` is


Choose the correct alternative:

The values of m for which the line y = `"m"x + 2sqrt(5)` touches the hyperbola 16x2 – 9y2 = 144 are the roots of x2 – (a + b)x – 4 = 0, then the value of (a + b) is


Share
Notifications



      Forgot password?
Use app×