Question

a metal pipe 63 cm long has an inner diameter 6 cm and outer diameter 7 cm . if the metal weight 7.5g per cm cube , find the weight of the metal pipe .

Answer 1

A/Q, Volume of the metal pipe = πh(r^2 - r•^2)
==> 22/7 × 63 {(7/2)^2 - 9}
==> 22 × 9 {(49/4)-9}
==> 22 × 9 × 13/4
==> 11 × 9 × 13/2
==> 643.5 cm cube

Now , Weight of the metal pipe in 1 cm cube = 7.5g
==> In 643.5cm cube , weight = (643.5 × 7.5)g
= 4826.25 g