Question

10. Find the volume of iron in a 20 cm long iron pipe
whose interior and exterior diameters measure 8 cm
and 10 cm respectively. (Take = 3.14)
​

Answer 1

Step-by-step explanation:

Let r,R and h be the inner, outer radii and height of the hollow cylindrical pipe respectively.

Given that 2r=6cm, 2R=8cm, h=28cm

Now, the volume of the pipe, V=π×h×(R+r)(R−r)

∴ Volume, V=616cu.cm

Weight of 1cu.cm of the metal =7gm

Weight of the 616cu.cm of metal =7×616gm

Thus, the weight of the pipe =4.312kg