The pipe

The pipe is 1.5 m long. Its outer diameter is 60 cm, inner diameter is 52 cm. Calculate the pipe's weight if the material's density from which it is made is 2 g/cm³. Please round the results to whole kilograms.

Correct answer:

m =  211 kg

Step-by-step explanation:

$$\begin{gathered} D_1=60\text{cm} \\ {D}_2=52\text{cm} \\ l=1.5\text{m}\to \text{cm}=1.5\cdot 100\text{cm}=150\text{cm} \\ \rho =2/1000=\frac{1}{500}=0.002{\text{kg/cm}}^3 \\ {r}_1=D_1/2=60/2=30\text{cm} \\ {r}_2=D_2/2=52/2=26\text{cm} \\ S=\pi \cdot r_1^2-\pi \cdot r_2^2=3.1416\cdot 30^2-3.1416\cdot 26^2\doteq 703.7168{\text{cm}}^2 \\ V=S\cdot l=703.7168\cdot 150\doteq 105557.5132{\text{cm}}^3 \\ m=V\cdot \rho =105557.5132\cdot 0.002=211\text{kg} \end{gathered}$$

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