Approximately 6361

The glass paperweight has the face of a sphere with a radius of 4 cm. Estimate and then calculate its weight. The density of glass is approximately 3800 kg/m³.

Correct answer:

m =  1.0187 kg

Step-by-step explanation:

$$\begin{gathered} r=4\text{cm}\to \text{m}=4:100\text{m}=0.04\text{m} \\ h=3800{\text{kg/m}}^3 \\ V=\frac{4}{3}\cdot \pi \cdot r^3=\frac{4}{3}\cdot 3.1416\cdot 0.04^3\doteq 0.0003{\text{m}}^3 \\ m=h\cdot V=3800\cdot 0.0003=1.0187\text{kg} \end{gathered}$$

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