Question

A metal pipe has a bore(internal diameter)
of 14 cm.The pipe is 1 mm of thick all
around.Find the weight of a pipe
if 1 cm 3 of the metal has 10 gm.

Answer 1

Answer:

internal diameter= 14 CM

internal radius= 14/2 CM

internal radius= 7 CM

thickness= 1 mm = 0.1 CM

outer radius = (7+0.1) CM

outer radius= 7.1 CM

outer volume=

$= \pi {r}^{2}h$

$\frac{22}{7} \times 7.1 \times 7.1 \times h$

$\frac{22}{7} \times 50.41 \times h$

inner volume =

$= \pi {r}^{2} h$

$( = \frac{22}{7} \times 7 \times 7 \times h) {cm}^{3}$

$(= 154h) {cm}^{3}$

VOLUME OF PIPE= OUTER VOLUME- INNER VOLUME

VOLUME OF PIPE=

$(154h - \frac{22}{7} \times 50.41h) {cm}^{3}$

$= 325.568571 {cm}^{3}$

$weight \: of \: 1 {cm}^{3} of \: pipe = 10g$

$weight \: of \: 325.568571 {cm}^{3}of \: pipe \: = (325.568571 \times 10)gm$

$= 3255.68571gm$