En matemáticas, un conjunto contable es un conjunto con la misma cardinalidad (número de elementos) que un subconjunto del conjunto de números naturales. Un conjunto contable es un conjunto finito o un conjunto contable infinito.
Answer:
Step-by-step explanation:
2.A
Answer:
940.8 N
1254.4 N
Step-by-step explanation:
I would think the questions would be to calculate the forces at the top of the cube and at the sides. Thus:
On the top:
F = pressure * area
P = density * gravity * height
the height would be:
1m - 0.4m = 0.6m
replacing:
P = 1000 * 9.8 * 0.6 = 5880
A = (0.4) ^ 2 = 0.16
F = 5880 * 0.16
F = 940.8 N
On the sides:
dF = d * g * h * dA
dA = 0.4 * dh replacing
dF = 1000 * 9.8 * h * 0.4 * dh
dF = 3920 * h * dh
We integrate both sides and we have:
F = 3920 * (h ^ 2/2), h = 0.6 up to h = 1
F = (3920/2) * (1 ^ 2 - 0.6 ^ 2)
F = 1254.4 N
