Your father and your younger brother are confronted with the same puzzle. Your father’s garden sprayer and your brother’s water cannon both have tanks with a capacity of 5.00 L (Fig. P18.18). Your father puts a negligible amount of concentrated fertilizer into his tank. They both pour in 4.00 L of water and seal up their tanks, so the tanks also contain air at atmospheric pressure. Next, each uses a hand-operated pump to inject more air until the absolute pressure in the tank reaches 2.40 atm. Now each uses his device to spray out water—not air—until the stream becomes feeble, which it does when the pressure in the tank reaches 1.20 atm. To accomplish spraying out all the water, each finds he must pump up the tank three times. Here is the puzzle: most of the water sprays out after the second pumping. The first and the third pumping-up processes seem just as difficult as the second but result in a much smaller amount of water coming out. Account for this phenomenon.
Figure P18.18
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Physics for Scientists and Engineers
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- I've posted the below question earlier, and I received the answer. This is the question: A J-shaped tube is filled with air at 760 Torr and 22 °C. The long arm is closed off at the top and is 100.0 cm long; the short arm is 40.00 cm high. Mercury is poured through a funnel into the open end. When the mercury spills over the top of the short arm, what is the pressure on the trapped air? Let h be the length of mercury in the long arm. I need further explanation of one step: - when P2 is obtained in the short arm, the equation is 40-h+P1 1. How did we get this equation? 2. the short arm does not contain any air, why do we create an equation of P2 in the short arm? Please clarify these concerns. I have received the answer shown in the attached picture but it is not correct.arrow_forwardAtmospheric pressure atop Mt. Everest is 4 2 3.30x10 N/m . (a) What is the partial pressure of oxygen there if it is 20.9% of the air? (b) What percent oxygen should a mountain climber breathe so that its partial pressure is the same as at sea level, where atmospheric pressure is 1.01 × 10^5 N/m^2 ?arrow_forwardWeek 4 #10 A scuba diver is in fresh water has an air tank with a volume of 0.0100 m3. The air in the tank is initially at a pressure of 1.00 × 107 Pa. Assume that the diver breathes 0.500 L/s of air. Density of fresh water is 1.00 × 103 kg/m3. How long will the tank last at depths of 4.80 m? _____minarrow_forward
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