Find the mass of a pine block 10 cm long, 5 cm wide, 2 cm thick, the density of pine is 400 kg / m.

Initial data: a (length of a pine block) = 10 cm; b (width of a pine block) = 5 cm; s (pine block thickness) = 2 cm.

Reference values: according to the condition ρс (pine density) = 400 kg / m3.

SI system: a = 10 cm = 0.1 m; b = 5 cm = 0.05 m; s = 2 cm = 0.02 m.

1) Let’s calculate the volume that the pine block occupies: V = a * b * s = 0.1 * 0.05 * 0.02 = 0.0001 m3.

2) Determine the mass of a pine bar: m = ρс * V = 400 * 0.0001 = 0.04 kg = 40 g.

Answer: The mass of a pine block is 40 grams.