complete

procedure

arbitrary

completely

switched

functional

responses

initial

determine

applied K. determined L. frequently We now consider those RLC circuits in which DC sources are 1 into the network and produce forced 2 that do not necessarily vanish as time becomes infinite. The general solution is obtained by the same 3 that was followed in RL and RC circuits: the forced response is 4 completely; the natural response is obtained as a suitable 5 form containing the appropriate number of 6 constants; the 7 response is written as the sum of the forced and the natural responses; and the 8 conditions are then determined and 9 to the complete response to find the values of the constants. It is this last step which is quite 10 the most troublesome to students.

景观美化

水土保持

固土护坡

美化环境

正确

错误

13

15

18

23

nickel

hundreds

coil

vacuum

classified

nonmagnetic

pass

provides

field

materials K. path L. vocum M.classify An inductor is basically a 1 of wire. The material around which the coil is formed is called the core. Coils are wound on either 2 or magnetic materials. Examples of nonmagnetic 3 are air, wood, copper, plastic, and glass. The permeabilities of these materials are the same as for a 4 . Examples of magnetic materials are iron, 5 , steel, cobalt, or alloys. These materials have permeabilities that are 6 or thousands of times greater than that of a vacuum and are 7 as ferromagnetic. A ferromagnetic core 8 a better 9 for the magnetic lines of force and thus permits a stronger magnetic 10 .