Phụ tải ba pha gồm ba cuộn dây giống nhau có r=8, x=6 nối hình tam giác, đặt vào điện áp ba pha đối xứng có ud=220v. Tính dòng điện các pha, dòng điện dây, hệ số công suất và công suất tác dụng ba pha?

Scout feels ill one day before school. her mother puts a thermometer in her mouth and the temperature begins to climb to 100°f. what is happening between the cooler thermometer and scout's body? a) scout's body is applying a force to the particles in the thermometer. b) kinetic energy is being transferred from her mouth to the thermometer. c) potential energy is being lost by the thermometer and gained by scout's body. d) the potential energy stored in foods is converted to mechanical energy to raise the mercury in the thermometer.

Arowboat passenger uses an oar to push the boat off the dock by exerting a force of 40n for 3.0s. what impulse acts on the boat.

Ametal ring 4.20 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. these magnets produce an initial uniform field of 1.12 t between them but are gradually pulled apart, causing this field to remain uniform but decrease steadily at 0.240 t/s . (a) what is the magnitude of the electric field induced in the ring? (b) in which direction (clockwise or counterclockwise) does the current flow as viewed by someone on the south pole of the magnet?