Q16 of 48 Page 1

A hollow sphere of internal and external radii 2 cm and 4 cm respectively is melted into a cone of base radius of 4 cm. Find the height and slant height of the cone.

Concept Used: Volume of a sphere


The volume of a cone


Where, r = radius and h = height.


When melting one solid into other, the volume remains same.


Given: Internal radii of sphere = 2 cm


External radii of sphere = 4 cm


Base radius of cone = 4 cm


Explanation:


⇒ The volume of material in sphere = Volume of the cone




⇒ h = 8 cm


Now, we have to calculate slant height of the cone,


l2 = h2 + r2


Putting the value of “r” and “h” in the


⇒ l = √(82 + 42)


⇒ l =√80 = 8.94 cm


Hence, The slant height of the cone is 8.94 cm.


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