Irodov – Problems in General Physics

A

0—•

Rj Ry

Fig. 3.49.

c Ri

Fig. 3.50.

3.185. Find the current flowing through the resistance R 1 of the

circuit shown in Fig. 3.48 if the resistances are equal to R 1 = 10 52,

R2 = 20 52, and 113 = 30 Q, and the potentials of points 1, 2, and 3

are equal to cp 1 = 10 V, •:P 2 = 6 V, and cp, = 5 V

R3

-4

62 --=-

Rz R, ,^0

R2

g 1

Fig, 3.47.

3

Fig. 3.48.

3.186. A constant voltage V = 25 V is maintained between

points A and B of the circuit (Fig. 3.49). Find the magnitude and

direction of the current flowing through the segment CD if the resist-
ances are equal to R 1 = 1.0 52, R2 = 2.0 0, R3 = 3.0 52, and R4 =
= 4.0 Q.
3.187. Find the resistance between points A and B of the circuit
shown in Fig. 3.50.
3.188. Find how the voltage across the capacitor C varies with
time t (Fig. 3.51) after the shorting of the switch Sw at the moment
t = 0.

Fig. 3.51. Fig. 3.52.

3.189. What amount of heat will be generated in a coil of resist-
ance R due to a charge q passing through it if the current in the coil
(a) decreases down to zero uniformly during a time interval At;
(b) decreases down to zero halving its value every At seconds?
3.190. A de source with internal resistance R 0 is loaded with
three identical resistances R interconnected as shown in Fig. 3.52.

9*