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3 Calculation problems, 10 points each . In a hydraulic lift, a force 10 N is applied to an input piston. What force is exerted on the output piston, if the area of output piston is 5 times larger than the area of the input piston? 12. Air is flowing through a duct with a velocity of 1 " . The cross-sectional area of the duct is 20 cm. What area of the duct would make the air to exit with a velocity of 2" ? Remember to convert units. 13. A heat engine takes 1.5 KJ of thermal energy from the hot reservoir and does uses 500 J of mechanical work in each operating cycle. Remember to convert units. a) How much heat is delivered to the cold reservoir in each cycle? b) What is the efficiency of the engine? 14. Two electric charges, qA = + 1 /C, 98 = + 3 /C are separated by a distance r = 30 cm. What is the force on charge B exerted by charge A? Remember that force is a vector (has magnitude and direction) and also about the unit conversion. 15. A 1.1-KW microwave oven and an 880-W coffee maker are plugged on the same circuit to a standard electric outlet, 110 V. The maximum current that can flow safely through the circuit is 15 A. Will the fuse protecting this circuit blow? Remember to convert units. 16. The circuit shown below is supplied by the 15-V battery. Calculate the total current flowing through the circuit, if the resistances are: RI = 10 02, R2 = 20 02, R3 = 30 02. R1 R2 R3 NA