Question

a conical hole is drilled in a circular cylinder of height 12cm and base radius 5 cm the height and the base radius of the cone are also the same find the total surface area of the solid remaining sides .​

Answer 1

SOLUTION

Given,

Base radius of Cylinder= 5cm

Height= 12cm

Let l be slant height of cone

=) l= √r^2+h^2

=)√5^2+ 12^2

=) √25+144

=) √169

=) l= 13

Height and base radius of cone and cylinder are same

Total surface area of remaining part

=) 2πrh +πr^2 + πrl

=) 2π (5)(12) + π(5)^2 +π(5)(13)

=) T.S.A= 210πcm^2

Volume of remaining part

=) volume of Cylinder- volume of cone

=) V= πr^2h - 1/3πr^2h

=)V= π(5)^2(12) - 1/3π(5)^2(12)

=) V= 200π cm^3

Therefore,

Volume of remaining part = 200πcm^3.

hope it helps ✔️❣️☺️