मराठी

An arch is in the form of a semi-ellipse. It is 8 m wide and 2 m high at the centre. Find the height of the arch at a point 1.5 m from one end. - Mathematics

Advertisements
Advertisements

प्रश्न

An arch is in the form of a semi-ellipse. It is 8 m wide and 2 m high at the centre. Find the height of the arch at a point 1.5 m from one end.

बेरीज
Advertisements

उत्तर

% In the figure, ELF is an arch whose width EF = 8 m and height = 2 m.

Let OX, OY be the coordinate axis. ELF is an ellipse with a = 4, b = 2

∴ Equation of ellipse,

`x^2/4^2 + y^2/2^2 = 1`

or `x^2/16 + y^2/4 = 1`

A point Q is at a distance of 1.5 m from end F.

∴ Distance of Q from O = 4 – 1.5 = 2.5 m

Let the height of the arch at point Q be P.

∴ P(2.5, P) lies on the ellipse.

∴ `(2.5)^2/16 + p^2/4 = 1`

or `p^2/4 = 1 - 6.25/16 = 9.75/16`

`p^2 = 9.75/16 xx 4 = 9.75/4`

`p = sqrt9.75/2`

= `3.122/2`

= 1.56 m (approximately)

Hence, the height of the arch at point Q = 1.56 m (approximately).

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 11: Conic Sections - Miscellaneous Exercise [पृष्ठ २६४]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 11
पाठ 11 Conic Sections
Miscellaneous Exercise | Q 4 | पृष्ठ २६४

संबंधित प्रश्‍न

Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

`x^2/36 + y^2/16 = 1`


Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

`x^2/4 + y^2/25 = 1`


Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

`x^2/100 + y^2/400 = 1`


Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

36x2 + 4y2 = 144


Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

16x2 + y2 = 16


Find the coordinates of the foci, the vertices, the length of major axis, the minor axis, the eccentricity and the length of the latus rectum of the ellipse.

4x2 + 9y2 = 36


Find the vertex, focus, axis, directrix and latus-rectum of the following parabola:

y2 = 8x 


Find the vertex, focus, axis, directrix and latus-rectum of the following parabolas 

y2 − 4y − 3x + 1 = 0 


Find the vertex, focus, axis, directrix and latus-rectum of the following parabola 

 y2 + 4x + 4y − 3 = 0 


Find the vertex, focus, axis, directrix and latus-rectum of the following parabola

y2 = 8x + 8


Find the vertex, focus, axis, directrix and latus-rectum of the following parabola 

x2 + y = 6x − 14


For the parabola y2 = 4px find the extremities of a double ordinate of length 8 p. Prove that the lines from the vertex to its extremities are at right angles. 


Find the length of the line segment joining the vertex of the parabola y2 = 4ax and a point on the parabola where the line-segment makes an angle θ to the x-axis.  


Write the axis of symmetry of the parabola y2 = x


Write the coordinates of the vertex of the parabola whose focus is at (−2, 1) and directrix is the line x + y − 3 = 0.

 


In the parabola y2 = 4ax, the length of the chord passing through the vertex and inclined to the axis at π/4 is


The vertex of the parabola (y − 2)2 = 16 (x − 1) is 


Find the centre, the lengths of the axes, eccentricity, foci of the following ellipse: 

x2 + 2y2 − 2x + 12y + 10 = 0 


Find the equation of the set of all points whose distances from (0, 4) are\[\frac{2}{3}\] of their distances from the line y = 9. 

 

If the lengths of semi-major and semi-minor axes of an ellipse are 2 and \[\sqrt{3}\] and their corresponding equations are y − 5 = 0 and x + 3 = 0, then write the equation of the ellipse. 


Write the eccentricity of the ellipse 9x2 + 5y2 − 18x − 2y − 16 = 0. 


If S and S' are two foci of the ellipse \[\frac{x^2}{a^2} + \frac{y^2}{b^2} = 1\] and B is an end of the minor axis such that ∆BSS' is equilateral, then write the eccentricity of the ellipse.


Given the ellipse with equation 9x2 + 25y2 = 225, find the major and minor axes, eccentricity, foci and vertices.


The equation of the circle having centre (1, –2) and passing through the point of intersection of the lines 3x + y = 14 and 2x + 5y = 18 is ______.


The equation of the circle which passes through the point (4, 5) and has its centre at (2, 2) is ______.


If the lines 3x – 4y + 4 = 0 and 6x – 8y – 7 = 0 are tangents to a circle, then find the radius of the circle.


Find the equation of a circle which touches both the axes and the line 3x – 4y + 8 = 0 and lies in the third quadrant.


Find the distance between the directrices of the ellipse `x^2/36 + y^2/20` = 1


The shortest distance from the point (2, –7) to the circle x2 + y2 – 14x – 10y – 151 = 0 is equal to 5.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×