The weight of a concrete block measuring 0.4 x 0.5 x 1 m is 5 kN. What is the density of the concrete.

Initial data: L (concrete block length) = 1 m; b (concrete block width) = 0.4 m; h (concrete block height) = 0.5 m; P (concrete block weight) = 5 kN (5000 N).

Reference values: g (acceleration due to gravity) ≈ 10 m / s2.

1) The mass of the concrete block: m = P / g = 5000/10 = 500 kg.

2) The volume of the concrete block: V = L * b * h = 1 * 0.4 * 0.5 = 0.2 m3.

3) Density of concrete: ρ = m / V = 500 / 0.2 = 2500 kg / m3.

Answer: According to the calculation, the density of concrete is 2500 kg / m3.