A cone of radius 6 cm has curved surface area 60π cm². How tall is it?

8 cm. πrl = 60π → 6l = 60 → l = 10 cm. Then h = √(10² − 6²) = √64 = 8 cm. (10 cm is the slant height, not the height.)

A cone of radius 6 cm has curved surface area 60π $cm^{2}$ . How tall is it?

Class 9Surface Area of a ConeMensuration

πrl = 60π →

6 l = 60

→

l = 10

cm. Then

h

= √

(1 0^{2} - 6^{2}) =

√64 = 8 cm. (10 cm is the slant height, not the height.)

Answer: B) 8 cm

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