One component of a metal sculpture consists of a solid cube with an edge of length 35.1 cm. The alloy used to make the cube has a density of 6910 kg / m3. Find the cube's mass.

Question

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Answer 1

Density is equal to mass divided by volume.

D = m/v

Keep in mind the units must be the same. Therefore I will change the 35.1 cm length of one edge of the cube to 0.0351 m. Recall that V = l x w x h. For a cube, all of these values will be the same so V = l³.

V = (0.0351 m)³ = 0.4 x 10^-5 m³.

Now we solve for m:

m = D X V = 6910 kg/m³ x 0.4 x 10^-5 m³.= 0.299 kg.

Notice how the untis of m³. will cancel out leaving the unit of kg.