(I) How much charge flows from each terminal of a 12.0-Vbattery when it is connected to a 500- µF  capacitor?

(II) If 21.0 V is applied across the whole network of Fig. 19–63, calculate (a) the voltage across each capacitor and (b) the charge on each capacitor. C = 3.00 μF C2 = 4.00 μF C3 = 2.00 μF FIGURE 19-63 V= Problems 39 and 40. -21.0 V-

In the circuit shown in Fig. 19–93, C¡ = 1.0 µF, C2 = 2.0 µF, C3 = 2.4 µF, and a voltage_ Vab = 24 V is applied across points a and b. After C, is fully charged, the switch is thrown to the right. What is the final charge and potential differ- ence on each capacitor? ao C2 FIGURE 19-93 C3 Problem 97. bo

capacitor and take C = xe A/d and Q = CAV to investigate the charge as follows. Use typical values for a cylindrical axon of cell wall thickness d = 1.6 x 10-8 m, axon radius r = 2.0 x 10¹ μm, and cell-wall dielectric constant x = 2.2. Positive charge layer Negative { charge layer External fluid Axon wall membrane 1 O No O Internal fluid Axon radius = r + d Q (a) Calculate the positive charge on the outside of a 0.10-m piece of axon when it is not conducting an electric pulse. (Assume an initial potential difference of 7.0 x 10-2 v.) C How many K+ ions are on the outside of the axon assuming an initial potential difference of 7.0 x 10-2 V? K+ ions Is this a large charge per unit area? Hint: Calculate the charge per unit area in terms of electronic charge e per angstrom squared (A2). An atom has a cross section of about 1 A² (1 A = 10-10 m). (Compare to normal atomic spacing of one atom every few A.) Yes

(II) Two parallel plates, connected to a 45-V power supply,are separated by an air gap. How small can the gap be if theair is not to become conducting by exceeding its breakdownvalue of E = 3 x 106 V/m?

A particular 12 V car battery can send a total charge of 84Ah (ampere-hours) through a circuit, from one terminal to the other. (a) How many coulombs of charge does this represent? (Hint: See Eq. 21-3.) (b) If this entire charge undergoes a change in electric potential of 12 V, how much energy is involved?

(III) Two resistors and two uncharged capacitors are arranged as shown in Fig. 19–72. Then a potential difference of 24 V is applied across the combination as shown. (a) What is the potential at point a with switch S open? (Let V = 0 at the negative terminal of the source.) (b) What is the potential at point b with the switch open? (c) When the switch is closed, what is the final potential of point b? (d) How much + charge flows through 24 V 8.8 N 0.48 μF a S the switch S after it is closed? 4.4 2 0.36 μF FIGURE 19–72 Problem 58.

9:21 25) O MOGD شهد قبل دقیقتين A solid cylindrical conductor of radius 2.1 cm is coaxial with a cylindrical shell of negligible thickness, radius 23 cm. Find the capacitance in units of nf) of this cylindrical capacitor if its length is 38.6 m.

a) Pind total capaeitane when You are giran a e g-volt batteny wnd five initally unakrangia er uf capaetors rt sc nd fotal capacitanee whin gou conneet all five capaeitors to the battery. In serfes 6) Flind total amount of charges that can capacitor. be stered in thisi