Two circles of radii 10 cm and 5 cm touch each other externally at point A. PQ is the direct common tangent of those two circles of centers O1 and O2 respectively. The length of PQ is equal to:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 10 cm.
We two circles touch externally then, the length of PQ = 2√(r1 × r2)
⇒ PQ = 2√(10 × 5)
⇒ PQ = 2√(5 × 2 × 5)
⇒ PQ = 10√2 cm