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MathsMediumMCQ2019 · 12 Apr Shift 1

Q69.If the angle of intersection at a point where the two circles with radii 5 cm and 12 cm intersect is 90°, then the length (in cm) of their common chord is: (1) 120 (2) 60 13 13 13 13 (3) (4) 5 2

What This Question Tests

This question combines the concept of orthogonal circles with the geometry of intersecting circles to determine the length of their common chord using geometric properties and the Pythagorean theorem.

Concepts Tested

Equation of a common chordAngle of intersection of circlesDistance between centersPythagorean theorem

Formulas Used

d² = r₁² + r₂² (for orthogonal circles)

Length of common chord formula

📚 NCERT Sections This Tests

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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.