+3 votes
in Class 10 by kratos

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

1 Answer

+5 votes
by kratos
 
Best answer

Given,

The internal radius of hollow sphere = 2 cm

The external radius of hollow sphere = 4 cm

We know that,

Volume of the hollow sphere 4/3 π × (43 – 23) … (i)

Also given,

The base radius of the cone = 4 cm

Let the height of the cone be x cm

Volume of the cone 1/3 π × 42 × h ….. (ii)

As the volume of the hollow sphere and cone are equal. We can equate equations (i) and (ii)

So, we get

4/3 π × (43 – 23) = 1/3 π × 42 × h

4 x (64 – 8) = 16 x h

h = 14

Now,

***** height of the cone (l) is given by

l = √(h2 + r2)

l = √(142 + 42) = √212

l = 14.56 cm

Therefore, the height and ** height of the conical heap are 14 cm and 14.56 cm respectively.*

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