volume = π r^2 h
volume of "solid" = π(6^2)(210) = 7560π cm^3
volume of part to be taken out = π(5^2)(210) = 5250π cm^3
volume of your pipe = 7560π cm^3 - 5250π cm^3
= 2310π cm^3
mass = 2310π(7.8) g = appr 56605.2 g or appr 56.6 kg
I used the actual value of π
on my calculator, why use 22/7 for π in 2021 ?
If you insist on using 22/7 redo the calculations
find the mass of a cylindrical iron pipe 2.1m long and 12cm in external diameter,of the metal is 1 cm thick and of density 7.8g/cm3 (take π=22/7)
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