MP Board · Class 9 · Mathematics · Surface Areas and VolumesThe curved surface area of a cone of radius $r$ and slant height $l$ is:
Step-by-Step Solution
The curved surface area of a right circular cone is given by the formula $\pi r l$, where $r$ is the radius of the base and $l$ is the slant height. Therefore, the correct option is $\pi r l$.
Detailed Options Breakdown
Option : 2\pi r l
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
Option 1: \pi r(r + l)
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
Option 2: \pi r l (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Option 3: \frac{1}{3}\pi r^2 h
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
💡 Study Guide: This question tests core syllabus concepts from Surface Areas and Volumes. For formulas, key summaries, and mock exam reference guides, read the full Surface Areas and Volumes Revision Notes.