Question

A toy is made in the form of hemisphere surmounted by a right cone whose circular base is joined with the plane surface of the hemisphere. the radius of the base of the cone is 7cm and it's volume is 3/2 of the hemisphere calculate the height of the cone and the surface area of the toy correct to 2 places of the decimal [take π=3 1/2] plzz give me the solution....

Answer 1

Thr radius of cone or hemisphere = 7 cm

suppose the height of cone = h cm
GIVEN :

volume of cone = 3/2 volume of hemisphere

=> 1/3 × 31/2 ×7×7 × h = 3/2 × 2/3 × 31/2 ×7×7×7

=> so ,..................................h = 21

now

=> slant height of cone = 22.135 cm

=> surface Area of toy = surface area of cone + surface area of hemisphere

=> 31/2 ×7 [ 22.135 + 14 ]

=> 2435.81 cm2
I hope it may helps u :-)

Answer 2

Continuation...


Surface area of the toy = 542.185+343 = 885.185 cm².

:)