Density 67774

The prism, whose base is square / the side of the square is 20 cm / 30 cm high, is made of oak wood, and weighs 8.5 kg. What is the density of oak wood?

Correct answer:

ρ =  708.3333 kg/m³

Step-by-step explanation:

$$\begin{gathered} m=8.5\text{kg} \\ a=20\text{cm}\to \text{m}=20:100\text{m}=0.2\text{m} \\ c=30\text{cm}\to \text{m}=30:100\text{m}=0.3\text{m} \\ V=a\cdot a\cdot c=0.2\cdot 0.2\cdot 0.3=\frac{3}{250}=0.012{\text{m}}^3 \\ \rho =m/V=8.5/0.012=708.3333{\text{kg/m}}^3 \end{gathered}$$

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