A hollow iron pipe is 2 m long. Its external diameter is 10 cm and it is 1 cm thick. Calculate the weight of
the pipe if iron weighs 8.2 g/cm3
.
+128475 The volume of the pipe is just the difference in the volumes of two cylinders =
Volume of "outside" cylinder - Volume of "inside" cylinder =
{2m = 200cm)
pi * ( 11/2)^2 * 200 - pi * (10/2)^2 * 200 =
200pi [ 5.5^2 - 5^2 ] =
200pi * 5.25 =
1050 pi cm^3
So....the weight is
1050 pi cm^3 * (8.2)g / cm^3 = [8610 pi] g ≈ 27049 g
Hey CPhill!
I don't get the part where
pi * ( 11/2)^2 * 200 - pi * (10/2)^2 * 200 =
can u please explain thanks.
+36916 I think that should be 9/2 rather than 11/2
like this:
pi * ( 10/2)^2 * 200 - pi * (9/2)^2 * 200
