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There is a monument. The total mass of the upper stone is 100t, and the height of the lower cornerstone is 1m. If the density of the cornerstone is 2 * 10 cubic kg / m3, and if the ground can bear the pressure of 68600, what is the bottom area of the cornerstone at least Another question: a piece of wood has a density of 400kg / m3 and a volume of 0.000056 m3. Put a frog on the block and the block floats on the water. The upper surface of the block is just level with the water surface. How much does the frog weigh?
The mass of the monument: m monument = 100t = 100000Kg
The gravity of the monument: G monument = m monument g = 100000kgx10n / kg = 1000 000 n
Maximum allowable pressure on the ground: F = PS = 50000pa x
P＝F/S
P = (g tablet + G base) / S
P = (g tablet + m base g) / S
P = (G + p-base V-base g) / S
P = (G + ρ base SHG) / S
50000＝（1000 000+2000 x S x 1 x 10）/S
50000S=1000 000+20000S
30000S=1000 000
S=33.33(m²)
The base area of the footstone shall be at least 33.33 square meters
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