Q69.If the circle x2 + y2 −6x −8y + (25 −a2) = 0 touches the axis of x, then a equals. (1) 0 (2) ±4 (3) ±2 (4) ±3
What This Question Tests
The question requires applying the condition that a circle touches the x-axis, which means the radius of the circle must be equal to the absolute value of its y-coordinate of the center.
Concepts Tested
Formulas Used
For x^2+y^2+2gx+2fy+c=0, center is (-g, -f), radius is sqrt(g^2+f^2-c)
Circle touches x-axis if r = |-f|
📚 NCERT Sections This Tests
6.11 — Dynamics Of Rotational
Physics Class 11 · Chapter 6
6.11 Dynamics of rotational the motion of extended bodies. motion about a fixed axis A large class of problems with extended bodies can be
9.15 — Apply Mirror Equation And The Condition:
Physics Class 12 · Chapter 9
9.15 Apply mirror equation and the condition: (a) f < 0 (concave mirror); u < 0 (object on left) (b) f > 0; u < 0 (c) f > 0 (convex mirror) and u < 0 (d) f < 0 (concave mirror); f < u < 0 to deduce the desired result.
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
📋 Question Details
- Chapter
- Circles
- Topic
- Equation of a circle
- Year
- 2013
- Shift
- 23 Apr Online
- Q Number
- Q69
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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