Q. A cone is formed by rolling a sector of radius 21 cm having a central angle of 120°. The base radius of the cone is:
✅ Correct Answer: (B)
7 cm
Explanation: Arc length = (120/360) × 2π × 21 = 14π = 2πr, so r = 7 cm.
Explanation by: Krishna Sharma
Arc length = (120/360) × 2π × 21 = 14π = 2πr, so r = 7 cm.