get app

Go To Your Study Dashboard

An iron pipe 20 cm long has exterior diameter equal to 25 cm . If the thickness of the pipe is 1 cm , find the whole surface of the pipe .

Answers (1)

D Deependra Verma

solution: $R=$ External radious $=$ $12$ .5 c

$Rightarrow$ $r=$ Internal radious $=$ External radius - thickness) = ( $12$ .5 - 1) $=$ 11.5 c

$Rightarrow$ h $=$ Length of the pipe $=$ 20 cm

$herefore$ Total surface areaof the pipe $=$

(External curved surface)+(Internal curver surface) + 2(Area of the base of the ring)

$=$ $2pi Rh+2pi rh+ 2(pi R^2-pi r^2)$

$=2pi (R+r)h +2pi (R^2-r^2)$

$=2pi (R+r)h +2pi(R+r)(R-r)$

$=2pi(R+r)(h+R-r)$

$=2 imes frac227 imes (12.5+11.5) imes (20+12.5-11.5)cm^2=2 imesfrac227 imes 24 imes21 cm^2$

$=3168 cm^2$

Similar Questions

Latest Asked Questions

Most Viewed Questions

Preparation Products

Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 40000/-

Buy Now

Knockout NEET 2025

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 45000/-

Buy Now

NEET Foundation + Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 54999/- ₹ 42499/-

Buy Now

NEET Foundation + Knockout NEET 2024 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-

Buy Now

NEET Foundation + Knockout NEET 2025 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-

Buy Now

Boost your Preparation for JEE Main with our Foundation Course

Start Now

Exams

Articles

Questions