Hãy xác định điện áp ngõ ra Về và các dòng điện chạy qua các điện trở như hình bên.
Già sử R, = 5k1, R2 = 10kN, V, = 0.7V, V+ =
+5V, Vº = -5V,0 = 0;
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Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?