2.219. AS = q1111T 2 -i-- CI, in (T2 /T1).
2.220. (a)
0.37; (b) i1
0.23.
2.221. X, = A//ln 1.
2.222. (a) P = e-at; (b) (t) = 1/a.
2.223. (a) X. = 0.06 p,m, ti = 0.13 ns; (b) X = 6 Mm, i = 3.8
hours.
2.224. 18 times.
2.225. X = (221./VA /3b)2/3 (kTolVITP0) = 84 nm.
2.226. v = 3td2poN AY 2T/MRT 0 = 5.5 GHz.
2.227. (a) 0.7 Pa; (b) 2.1014 cm-3, 0.2 p.m.
2.228. (a) v =1/- 2-xt den (v) = 0.74 • 10'°
(b) v = 1/2 1/ - 2n d2n2 (v) 1.0 X 1029 s -1 • cm-3, where n = po/kTo,
8RTITEM.
2.229. (a) = const, v oc 117'; (b) X oc T, v c 1/j/T.
2.230. (a) X, = const, v increases .
1777, times; (b) X, decreases n
times, v increases n times.
2.231. (a) X oc V, v oc V-615; (b) X oc p-5/Y, v oc p°17; (c)
oc
oc T-5/2, v cc T3.
2.232. (a) ) cc V, v oc V-(n+1112; (b) X cc p-1/n, v cc p(n+1)/2n;
(c) k cc T 1/(1-- n), v oc T(ni-1)/2(n-1) .
2.233. (a) C = 1/4R (1 + 2i) = 23 J/(K•mol); (b) C
1 12R (i + 2) = 29 J/(K •mol).
2.234. n = noe-t/t, where T.= 4V /S (v), (v)=-1/ 8RTIaM.
2.235. Increases (1 -I- '0/(1 H-1/j) times.
2.236. Increases a3/f3 = 2 times.
2.237. (a) D increases n times,
= const; (b) D increases
n3/2 times, rl increases V n times.
2.238. D decreases n4/5
6.3 times, 11 increases ni/5
1.6 times.
2.239. (a) n -- 3; (b) n = 1; (c) n = 1.
2.240. 0.18 nm.
2.241. dAr/dHe = 1.7.
2.242. N1 2wriaiR3/AR; p =
kTInclznAR = 0.7 Pa.
2.243. rl = (1/R2 , — 1/4 N1/4no).
2.244. N = 1/2wrio)a4/h.
2.245. N ='13(oa4p aMI2RT.
2.246.
aa4 M i PI — Pi
Ix = HIRT
/
2.247. T
x2T2112)1(x1ll1
x282).
2.248. x = (11
/2)/(i1ix1 4- 12/x2).
2.249. T (x) = T1 (T 21T 1)4; q = (all) in (T2/T1)2.250. AT = (AT)0e-c", where a = (1/C1 + 1/C2) Sx//.
2.251. T = T 1 {1
(x/l) [(T 217'1)312 — 11)2/3 , where x is the distance from the plate maintained at the temperature Ti.
20-9451