In a water pistol, a piston drives water through a larger tubeof radius 1.30 cm into a smaller tube ofradius 1.30 mm as in the figure below.
A diagram shows the interior of a water pistol pointing to theright, and the flow of water through it. The left end of thetrigger is connected to the piston on the right end of a cylinder.The left end of the cylinder is connected to a tube, such thatwater within the cylinder can exit through the tube. The tubestarts at the cylinder, extends to the left, curves upward and tothe right, and extends horizontally to the right until the end ofthe tube reaches the nozzle of the pistol. The cross-sectionalareas of the cylinder and tube arelabeled A1 and A2,respectively. An arrow labeledvector F to the right of the triggerpoints to the left toward the trigger. The velocities of waterwithin the cylinder and water ejected from the nozzle are labeledvector v1 andvector v2, respectively.
(a) If the pistol is fired horizontally at a heightof 1.40 m, use ballistics to determine the time it takeswater to travel from the nozzle to the ground. (Neglect airresistance and assume atmospheric pressure is 1.00atm. Assume up is thepositive y-direction. Indicate the directionwith the sign of your answer.) s(b) If the range of the stream is to be 8.50 m, with whatspeed must the stream leave the nozzle? m/s(c) Given the areas of the nozzle and cylinder, use the equation ofcontinuity to calculate the speed at which the plunger must bemoved. m/s(d) What is the pressure at the nozzle? (Give your answer to atleast four significant figures.) Pa(e) Use Bernoulli's equation to find the pressure needed in thelarger cylinder. PaCan gravity terms be neglected?
YesNo
(f) Calculate the force that must be exerted on the trigger toachieve the desired range. (The force that must be exerted is dueto pressure over and above atmospheric pressure. Entermagnitude.) N
atm. Assume up is the positive y-direction. Indicate thedirection with the sign of your answer.) s (b) If the range of thestream is to be 8.50 m, with what speed must the stream leave thenozzle? m/s (c) Given the areas of the nozzle and cylinder, use theequation of continuity to calculate the speed at which the plungermust be moved. m/s (d) What is the pressure at the nozzle? (Giveyour answer to at least four significant figures.) Pa (e) UseBernoulli's equation to find the pressure needed in the largercylinder. Pa Can gravity terms be neglected? Yes No (f) Calculatethe force that must be exerted on the trigger to achieve thedesired range. (The force that must be exerted is due to pressureover and above atmospheric pressure. Enter magnitude.) N
In a water pistol, a piston drives water through a larger tube of radius 1.30 cm into a smaller tube of radius 1.30 mm a
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