Q1 of 38 Page 257

A drinking glass is in the shape of a frustum of acone of height 14 cm. The diameters of its two circular ends are 4 cm and 2 cm. Find the capacity of the glass

Given:

Radius (r1) [Upper base] =


= 2 cm


Radius (r2) [Lower base] = = 1 cm


Capacity of glass = Volume of frustum of cone


= h (r12 + r22 + r1r2)


= h [(2)2 + (1)2 + (2) (1)]


= * * 14 [4 + 1 + 2]


=


= 102 cm3


Hence, the capacity of the glass = 102 cm3


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