Irodov – Problems in General Physics

3.318.

/iDpm ' o

= 0.7 ms, where p is the resistivity, po is the

density of copper.

3.319. Li — 1/ 2 :: In = 0.26 p,H/m. 1

3.320. L p,N 2 a In (1 +1).

3.321. L 1 = ti oldb = 25 nH/m.

3.322. Li Pi'. In 1.

3.323. (a) I = na 2 B/L; (b) A = 1/2n2a4B2/L.

3.324. I = I (1 + = 2 A.

3.325. / = jia 8 B — 50 A.

[to ln — 2 )

3.326. I= + (1— 1) e-tliR/L].

3.327. I =1- (1— e —t-R/ 2 9.

3.328. 1., " (^) R (.1, 1 L+L2) 2
3.329. Lie= 4 12 ' 1 In (1 -1-÷).
3.330. Li2

p, 0

2N

in b

3.331. (a) L 1

2

(^1) / 2 11, 03 - ta 2 /b; (b) 0 21 = 11 21-Lona 2 //b.
3.332. pm = 2aRqlp,oN.
3.333. L 12 ^---% 112 p,ona 4113.
3.334. /2 = aLR12 (1 e-tR/L2).
3.335. /4^2
Q 2R 2 (1+ Rol R) —3
J.
3.336. W = 0.5 J.
3.337. W = BlIa 2 a 2 b = 2.0 J, where H = 1 /2 NI/nb.
3.338. (a) Wgap/Wm pb/nd = 3.0; (b) L aN — di 2 0.15 H.
3.339. Wi = Rdt, 2 6) 2 a 2 /831.
3.340. E = (^) solo= 3.10^8 V/m.
3.341. wm/ive = go110002a 4/ 2^ 1.1.10-15.
3.343. (a) Ltotat = 2L; (b) Ltotat = L/2.
3.344. L12=1/- L1L2.
3.346. W12= P2b2 / 1 / 2 cos 0.
3.347. (a) ja = --i; (b) Id = qieogP•
3.348. The displacement current should be taken into account
in addition to the conduction current.
3.349. Em = Inzleo coS = 7 V/cm.
3.350. H = Hm cos (cot ±a,), where
and a is determined from the formula tan a = co m/a.
R' (Li+ L2)
117 n-72; V 62 + (8°"))2
319