Illustration : Through the vertex O of a parabola y 2 = 4x chords OP and OQ are drawn at right angles to one another. (ii) focus is (a,0) (iii) Axis is y = 0 (iv) Directrix is x + a = 0 (a) Focal distance : The distance of a point on the parabola from the focus is called the focal distance of the point. asked Nov 4, 2019 in Mathematics by SudhirMandal (53.5k points) parabola; 0 votes. Locus of midpoint of focal chord. a circle. Let the other end be a varaible point P given by (at2,2at). For this parabola : (i) Vertex is (0,0). a parabola. Locus of the midpoint of any focal chord of y^2 = 4ax is ... PQ is a chord of the parabola y^2 = 4ax such that the normals at P and Q intersect on the parabola. Find the locus of the middle points of the normal chords of the parabola y 2 = 4ax. an ellipse. If the parabola is Y 2 = 4ax take the focal chord which is easy for calculation e.x. The Vertex is O(0.0), which is one end of the chord. Show that for all position of P, PQ cuts the axis of the parabola at a fixed point. Also find the locus of the middle point of PQ. 1. or yy 1 – 2a(x + x 1) = y 1 2 – 4ax 1 or yy 1 – 2ax = y 1 2 – 2ax 1. Solution: Equation of the normal chord at any point (at 2, 2at) of the parabola is. y + tx = 2at + at 3. Then the midpoint of the chord PQ. A circle drawn on any focal chord of the parabola y2=4ax as diameter cuts parabola at two points ‘t’ and ‘t ’ (other than the extrimity of focal chord) the (a) tt = –1 (b) tt = 2 The locus of the mid-points of the focal chord of the parabola y 2 = 4ax is. Midpoint of OP is (at2/2,at). points P and Q. So, p = at2/2 and q = at. … (2) Let M(p,q) be the midpoint of the chord OP. (c) Double ordinate : Equation of chord to the given parabola with given mid point (2,1) is given by, T = S 1 *Multiple options can be correct. (b) Focal chord : A chord of the parabola, which passes through the focus is called a focal chord. is Y^2=4aX(standard eq.) B. 9. Locus of the mid–point of chord AB is (a) 22 2 2 4 22 xy ... 19. (Chords orthogonal at the vertex) Let PQ be a chord of a parabola with vertex O such that angle POQ is a right angle. … (1) Equation of the chord with mid point (x 1, y 1) is T = S1. Show that as the focal chord varies, the line PQ passes through a fixed point. This worksheet shows the locus of the midpoint of the focal chord of a parabola Find the locus of middle points of a family of focal chords of the parabola y^2=4ax Class: 11 2 See answers rohitkumargupta rohitkumargupta HELLO DEAR , Let the equation of the parabola be y2 = 4ax. 8. The extremities of a focal chord of the parabola y 2 = 4ax may be taken as the points t and − 1/t. The locus of the middle points of all chords of the parabola y 2 = 4ax passing through the vertex is. Hence locus of (α, β) is y2 = 2a(x – a). ... We have y 2 = 4 ax We know that ends of focal chord are at 2, 2 at and a t 2,-2 a t Let h, k be the mid point ... 2 h = at 2 + a t 2 ⇒ 2 h a = t 2 + 1 t 2 ⇒ 2 h a = t-1 t 2 + 2 a 2 + b … Find the locus of the midpoint of PQ. Let the parabola we consider and draw chords be y2 = 4ax. The locus of the mid point of the focal radii of a variable point moving on the parabola, y 2 =4ax is a parabola whose (A) vertex is (a/2,0) (B) Latus rectum is half the latus rectum of the original parabola (C) Focus has the co-ordinates (a,0) (D) Directrix is y-axis 2. a straight line. Find the locus of the middle point of focal chord of parabola whose eq. y 2 = a(x - a) y 2 = 2a(x - a) y 2 = 4a(x - a) None of these. QUESTION: 13. Normal chords of the chord with mid point ( x – a ) 22 2... Chord: a chord of the parabola at a fixed point parabola, which through. ) focal chord of the parabola y 2 = 4ax ) 22 2 2 22... Taken as the focal chord of parabola whose eq ; 0 votes 4ax is parabola... 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