Hobbies And Interests
Things You'll Need
Instructions
Turn on a digital laboratory scale. Press the "TARE" button of the scale to zero the scale. Follow manufacturer instructions for the scale if you do not know how to zero it.
Place a 500-milliliter laboratory graduated cylinder on the scale and record the weight of the graduated cylinder in grams. For example, the graduated cylinder weighs 420 grams.
Dip a 500-milliliter volumetric flask or small plastic bottle in the open tank to collect a sample of fluid. For example, dip a plastic bottle in an open tank of water and fill the bottle with water.
Remove the graduated cylinder from the digital scale and place it on a level surface. Insert the narrow end of a funnel in the mouth of the graduated cylinder. Pour the fluid sample from the flask or bottle through the funnel and into the graduated cylinder until the cylinder is half full.
Pour more fluid into the graduated cylinder until the bottom of the meniscus -- the upward-facing curve at the top of the liquid -- is even with the "500-ml" mark on the side of the graduated cylinder.
Remove the funnel from the mouth of the graduated cylinder. Place the graduated cylinder containing the fluid sample on the digital scale and record the weight displayed in grams. For example, the scale displays 920.00 grams. The combined weight of the graduated cylinder and water sample is 920 grams.
Subtract the weight of the empty graduated cylinder from the combined weight of the graduated cylinder and fluid sample using a calculator to find the weight of the fluid sample in grams. For example, 920 - 420 = 500. The weight of the water sample is 500 grams.
Divide the weight of the fluid sample in grams by 0.5 using a calculator to find the density of the fluid sample in kilograms per cubic meter. For example, 500/0.5 = 1,000. The density of the water in the open tank is 1,000 kilograms per cubic meter.
Divide the submerged height in feet of the open tank wall by 3.28 to convert the measurement to meters. For example, the submerged height of one wall is 6.56 feet, therefore, 6.56/3.28 = 2. The submerged height of the wall is two meters.
Divide the submerged width in feet of the open tank wall by 3.28 to convert the measurement to meters. For example, the submerged width of the wall is 9.84 feet, therefore, 9.84/3.28 = 3. The submerged width of the wall is three meters.
Square the height in meters of the submerged wall and divide the answer by 2. For example, (2 x 2)/2 = 2.
Multiply the answer by the submerged width of the wall in meters. For example, 2 x 3 = 6.
Multiply the answer by the acceleration of gravity. The acceleration of gravity at the surface of the earth is approximately 9.81 meters per second squared. For example, 6 x 9.81 = 58.86.
Multiply the answer by the calculated density of the fluid in the open tank in kilograms per cubic meter. For example, the density of the water in the open tank is 1,000 kilograms per cubic meter, therefore 58.86 x 1000 = 58860. Hydrostatic pressure on the wall of the open tank exerts a force of approximately 58,860 Newtons.