The foundation can withstand a pressure of 20 kPa. Is it possible to put a machine on it if its weight is 300 kg and the area of one of the four supports is 50 cm2.
Rf = 20 kPa = 20 * 10 ^ 3 Pa.
m = 300 kg.
g = 9.8 m / s2.
S1 = 50 cm2 = 0.005 m2.
N = 4.
The pressure of the force P is the ratio of the force F to the area S on which this force acts: P = F / S.
The table presses on the foundation with its weight F, the value of which is determined by the formula: F = m * g.
Since the machine has N legs, the area S, over which the machine’s weight is distributed, is expressed by the formula: S = N * S1.
P = m * g / N * S1.
P = 300 kg * 9.8 m / s2 / 4 * 0.005 m2 = 147000 Pa = 147 kPa.
We see that the pressure of the machine will be more than the allowable possible: P> Pf, so the machine cannot be placed on the foundation. To put the machine on the foundation, it is necessary to increase the area of the legs.
Answer: The machine must not be placed on the foundation.
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