Question 9. 9. A stick of length 10 units rests against the floor and a wall of a room. If the stick begins to slide on the floor then the locus of its middle points - (A) x2 + y2 = 2.5 (B) x2 + y2 = 25 (C) x2+ y2 = 100 (D) none Share with your friends Share 13 Mayank Jha answered this Dear student, Let the stick be AB with A on the wall and B on the floor. Assume that the vertical plane containing the stick is perpendicular to the wall.Let the point on the floor vertically below A be O. Then, ∠AOB = 90°Since, AB = 10 and it has constant length the distance from O to the mid-point M on AB has length 102=5.So, M lies on a circle center at O.Equation of the circle will be: x2 + y2 = 25 Hence, correct answer for this question will be option (B). Regards 9 View Full Answer