Air Pressure Normal sea level pressure is expressed as 1013.2 mb (millibars) of mercury (a way...

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Air Pressure Normal sea level pressure is expressed as 1013.2 mb (millibars) of mercury (a way of expressing force per square meter of surface area). At sea level standard atmospheric pressure is expressed in several ways: . . 1013.250 millibars 101.325 kilopascals (kilopascal = 10 millibars) . 14.7 lb/in² 29.9213" of Hg (mercury) Some convenient conversions are helpful: . . 1.0 in. (Hg) = 33.87 mb = 25.40 mm (Hg) = 0.49 lb/in² 1.0 mb = 0.0295 in. (Hg) = 0.75 mm (Hg) = 0.0145 lb/in² The standard atmosphere for pressure in millibars and altitude in kilometers is given in Table 7.1. This is used in the activity that follows the table. Table 7.1 Standard atmosphere for pressure and altitude Altitude (km) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Pressure (mb) 1013.25 954.61 898.76 845.59 795.01 746.91 701.21 616.60 540.48 472.17 411.05 356.51 308.00 Altitude (km) 10.00 12.00 14.00 16.00 18.00 20.00 25.00 30.00 35.00 40.00 50.00 60.00 70.00 Pressure (mb) 264.99 193.99 141.70 103.52 75.65 55.29 25.49 11.97 5.75 2.87 0.79 0.23 0.06 1. Using the graph in Figure 7.1, plot the standard atmosphere of air pressure decrease with altitude presented in Table 7.1. After completing the plot, connect the data points with a line to complete the pressure profile of the atmosphere. The data points from 0 to 5 km are plotted for you. Kilometers 70 60 50- 40 30 25 20 15 10 12 5 0 100 200 300 400 0 and 1 km 2 and 3 km 5 and 6 km 8 and 9 km 9 and 10 km Show conversion work here: [3.38] [114.49] mb; mb; 2.17 3.8 8.31 mb; 202 1.43 mb; 48.51 43.01 mb; 1.27 500 Millibars in. in. 600 700 in. in. in. 800 44 31 25 12.4 Figure 7.1 Atmospheric pressure profile graph-the standard atmosphere from the surface to 70 km. 2. The information in Table 7.1 allows a determination of the rate of pressure decrease with altitude, which is not at a constant rate. Remember that half of the weight of the total atmosphere occurs below 5500 m (18,000 ft); at that altitude only about half of the total atoms and molecules of atmospheric gases remain to form the mass of the atmosphere. Determine the decrease in pressure between the following altitudes. Ex- press the difference in millibars and inches of mercury. (Conversions are presented earlier in this section.) 1 km interval difference in pressure: 6.2 0 900 1013.2 Mies 10 km interval difference in pressure: 0 and 10 km [748.26] _mb; 10 and 20 km 209.7 mb; 20 and 30 km 43.32 mb; 40 and 50 km 2.08 60 and 70 km 0.17 [114.49 mbx.0295 in/mb = 3.38 in] [22.07] in. .19 in. 1.28 in. mb; 0.0 in. mb; 0.005 in. 3. Using the graph you prepared in Figure 7.1, approximate the answers to the following (assuming standard atmosphere conditions): a) Mount Everest's summit is 8850 m (29,035 ft) above sea level. What is the barometric pressure there [320 mb] according to the standard atmosphere? b) Mount McKinley, 6194 m (20,320 ft); air pressure at the summit? c) Mount Whitney, 4418 m (14,494 ft); air pressure at the summit? d) Yellowstone Lake, Yellowstone N.P., 2356 m (7731 ft); air pressure? e) The Petronas Towers I and II, Kuala Lumpur, Malaysia, 452 m (1483 ft); air pressure? 1) In a commercial airliner taking you from San Francisco to New York at 12,000 m (39,400 ft), what percentage of atmospheric pressure is below your plane? What percentage of atmospheric pressure resides above your flight altitude? Air Pressure Normal sea level pressure is expressed as 1013.2 mb (millibars) of mercury (a way of expressing force per square meter of surface area). At sea level standard atmospheric pressure is expressed in several ways: . . 1013.250 millibars 101.325 kilopascals (kilopascal = 10 millibars) . 14.7 lb/in² 29.9213" of Hg (mercury) Some convenient conversions are helpful: . . 1.0 in. (Hg) = 33.87 mb = 25.40 mm (Hg) = 0.49 lb/in² 1.0 mb = 0.0295 in. (Hg) = 0.75 mm (Hg) = 0.0145 lb/in² The standard atmosphere for pressure in millibars and altitude in kilometers is given in Table 7.1. This is used in the activity that follows the table. Table 7.1 Standard atmosphere for pressure and altitude Altitude (km) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Pressure (mb) 1013.25 954.61 898.76 845.59 795.01 746.91 701.21 616.60 540.48 472.17 411.05 356.51 308.00 Altitude (km) 10.00 12.00 14.00 16.00 18.00 20.00 25.00 30.00 35.00 40.00 50.00 60.00 70.00 Pressure (mb) 264.99 193.99 141.70 103.52 75.65 55.29 25.49 11.97 5.75 2.87 0.79 0.23 0.06 1. Using the graph in Figure 7.1, plot the standard atmosphere of air pressure decrease with altitude presented in Table 7.1. After completing the plot, connect the data points with a line to complete the pressure profile of the atmosphere. The data points from 0 to 5 km are plotted for you. Kilometers 70 60 50- 40 30 25 20 15 10 12 5 0 100 200 300 400 0 and 1 km 2 and 3 km 5 and 6 km 8 and 9 km 9 and 10 km Show conversion work here: [3.38] [114.49] mb; mb; 2.17 3.8 8.31 mb; 202 1.43 mb; 48.51 43.01 mb; 1.27 500 Millibars in. in. 600 700 in. in. in. 800 44 31 25 12.4 Figure 7.1 Atmospheric pressure profile graph-the standard atmosphere from the surface to 70 km. 2. The information in Table 7.1 allows a determination of the rate of pressure decrease with altitude, which is not at a constant rate. Remember that half of the weight of the total atmosphere occurs below 5500 m (18,000 ft); at that altitude only about half of the total atoms and molecules of atmospheric gases remain to form the mass of the atmosphere. Determine the decrease in pressure between the following altitudes. Ex- press the difference in millibars and inches of mercury. (Conversions are presented earlier in this section.) 1 km interval difference in pressure: 6.2 0 900 1013.2 Mies 10 km interval difference in pressure: 0 and 10 km [748.26] _mb; 10 and 20 km 209.7 mb; 20 and 30 km 43.32 mb; 40 and 50 km 2.08 60 and 70 km 0.17 [114.49 mbx.0295 in/mb = 3.38 in] [22.07] in. .19 in. 1.28 in. mb; 0.0 in. mb; 0.005 in. 3. Using the graph you prepared in Figure 7.1, approximate the answers to the following (assuming standard atmosphere conditions): a) Mount Everest's summit is 8850 m (29,035 ft) above sea level. What is the barometric pressure there [320 mb] according to the standard atmosphere? b) Mount McKinley, 6194 m (20,320 ft); air pressure at the summit? c) Mount Whitney, 4418 m (14,494 ft); air pressure at the summit? d) Yellowstone Lake, Yellowstone N.P., 2356 m (7731 ft); air pressure? e) The Petronas Towers I and II, Kuala Lumpur, Malaysia, 452 m (1483 ft); air pressure? 1) In a commercial airliner taking you from San Francisco to New York at 12,000 m (39,400 ft), what percentage of atmospheric pressure is below your plane? What percentage of atmospheric pressure resides above your flight altitude?

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3 a 320mb is given So in inches 320x00295944 in b Mount McKinley 6124m air pressure 460mb46000295 ... View the full answer