Question

7. Find the total surface area of a cylindrical pipe of thickness 2 em. The external diameter of the pipe is
21 cm and its length is 3 m.​

Answer 1

Answer:

We have,

Height of pipe (h)=300 cm

External diameter =21 cm

External radius (R)=21/2=10.5 cm

Internal diameter =21−(2+2)=17 cm

Internal radius (r)=17/2=8.5 cm

Total surface area

=2π(R+r)(R−r+h)

=2π(10.5+8.5)(10.5−8.5+300)

=2π(19)(302)

=11476$\pi \: cm ^{2}$

=11476 $\pi \: cm \:^{2}$

Hence, the total surface area of the cylinder =11476 π cm ^2

Step-by-step explanation:

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Done by Aritra kar.