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MathsMediumMCQ2021 · 31 Aug Shift 1

Q66.The line 12x cos θ + 5y sin θ = 60 is tangent to which of the following curves ? (1) x2 + y2 = 30 (2) 144x2 + 25y2 = 3600 (3) x2 + y2 = 169 (4) 25x2 + 12y2 = 3600

What This Question Tests

This question tests the ability to identify the conic section to which a given line is tangent by comparing its equation with standard tangent forms or using the tangency condition.

Concepts Tested

Equation of a tangent to an ellipseCondition for tangency

Formulas Used

Condition for y=mx+c to be tangent to x^2/a^2 + y^2/b^2 = 1 is c^2 = a^2m^2 + b^2

Equation of tangent x/a cosθ + y/b sinθ = 1

📚 NCERT Sections This Tests

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72% match

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71% match

2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.

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71% match

9.8 A beam of light converges at a point P. Now a lens is placed in the path of the convergent beam 12cm from P. At what point does the beam converge if the lens is (a) a convex lens of focal length 20cm, and (b) a concave lens of focal length 16cm?