Question

A metal pipe is 77 cm long. The inner diameter of a cross section is 4 cm, the outer diameter being 4.4cm. (see fig. 13.11). Find its

(i) inner curved surface area,

(ii) outer curved surface area

(iii) total surface area

(Assume π=22/7)​

Answer 1

Step-by-step explanation:

option 3 total surface area.

Answer 2

Step-by-step explanation:

i) Inner radius of cylindrical pipe = r1=

Inner diameter

2

cm = 2 cm

Height (h) of cylindrical pipe = 77 cm

Curved Surface Area of inner surface of pipe = 2πr,h

= (2 x (22/7) x 2 x 77) cm2

= 968 cm²

ii) Outer radius of cylindrical pipe =r 2

=

Outer diameter/2

=

(4.4/2) cm = 2.2 cm

Height of cylinder = h = 77 cm

Curved Surface Area of outer surface of pipe = 2πr 2 h

= (2x(22/7) 2.2 x 77) cm²

= (2 x 22 x 2.2 X 11) cm²

= 1064.8 cm²

Hope this helped you.. :)