Calculating Pressure from Stacked Bricks: Fluids Homework Solution

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To determine the minimum number of bricks needed to exert a pressure of at least one atmosphere on the ground, the area of the brick's face in contact with the ground must be calculated. The area is found by multiplying the dimensions of the brick, specifically using the smallest face to maximize pressure. The pressure is then calculated using the formula pressure = force / area, with the weight of the bricks contributing to the total force. The calculation must ensure that the total weight divided by the area meets or exceeds 101300 Pa, the equivalent of one atmosphere. The discussion emphasizes the importance of using the correct face area for accurate pressure calculations.
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Homework Statement


A brick weighs 15.0 N and is resting on the ground. Its dimensions are 0.203 m 0.0890 m 0.0570 m. A number of the bricks are then stacked on top of this one. What is the smallest number of whole bricks (including the one on the ground) that could be used, so that their weight creates a pressure of at least one atmosphere on the ground beneath the first brick? (Hint: First decide which face of the brick is in contact with the ground.)

pressure = force / area
density = Mass / volume
1atm = 101300 Pa
Volume = l* w* h





The Attempt at a Solution


well what i did was i found the area of the face to be .203 * .0890..then i divided 15/ Area to get pressure then i did 101300 / pressure to get number of bricks..this doesn't work
 
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To get max pressure, the area should be the least. Do you think you have found that correctly?

After that, total weight/area = pressure on the ground.
 
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