Question

QUESTION - 20. What will be the total surface of a hollow cylinder open at ends, if the length is 12 cm, the external diameter 10 cm and thickness 2 cm? *​

Answer 1

Answer:

Let outer radius be r2 and inner radius=r1, height be h

So total surface area=2*pi*h*(r2+r1) + 2*pi* (r2^2 -r1^2)

Since h=22cm, r2=7cm,r1=7–1=6cm

So total surface area=2*(22/7)*22*(13) + 2*(22/7)*(49–36)

=44*(13/7)*(23)

=1879.43cm^2

Step-by-step explanation:

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