如图甲所示电路是某自动恒温箱原理简图
\u3010\u516b\u5e74\u7ea7\u7269\u7406\u3011\u5982\u56fe\u6240\u793a\u7535\u8def\u662f\u5728\u73af\u5883\u6e29\u5ea6\u572810\u2103\u6761\u4ef6\u4e0b\u5de5\u4f5c\u7684\u67d0\u81ea\u52a8\u6052\u6e29\u7bb1\u539f\u7406\u7b80\u56feUab=R1/\uff08R1+R2\uff09=5*12/\uff085+R2\uff09
1\u3001Uab25\u5343\u6b27
2\u3001Uab>4,\u65ad\u5f00\uff0c\u6b64\u65f6\uff1aR2<10\u5343\u6b27
\u6839\u636e\u6e29\u5ea6\u53d8\u5316\u7684\u56fe\u7ebf\u5c31\u53ef\u4ee5\u5224\u65ad\u51fa\u6e29\u5ea6\u8303\u56f4\uff0c\u5355\u4ece\u4f60\u7684\u8868\u683c\u4e0a\u8bfb\u7684\u8bdd\u7b2c\u4e00\u9898\u662f25\u5343\u6b27\uff0c\u90a3\u6e29\u5ea6\u8303\u56f4\u662f\uff1a15-50\u6444\u6c0f\u5ea6
\u89c2\u5bdf\u8868\u683c\u53ef\u4ee5\u770b\u51faR2\u963b\u503c\u8d8a\u9ad8\uff0c\u6e29\u5ea6\u53d8\u5316\u8303\u56f4\u8d8a\u5c0f\uff0c\u800c\u4e14R1\u4e0d\u7528\u6570\u636e\u4ee3\u5165\u5f97\u5230R25R1\u65f6\u63a5\u901a\uff0c\u90a3\u4e48\u9002\u5f53\u589e\u52a0R1\u7684\u503c\u5c31\u80fd\u4f7f\u6e29\u5ea6\u53d8\u5316\u8303\u56f4\u51cf\u5c0f\u3002
\u89e3\uff1a(1)30 k \u03a9 (2)\u5f53U ab =2V \u65f6\uff1a\u7535\u963bR 1 \u4e0e\u7535\u963bR 2 \u4e32\u8054\uff0cR 2 \u4e24\u7aef\u7535\u538bU 2 =10V \u3002I=U ab \uff0fR 1 =2V\uff0f5000\u03a9=4\u00d710 -4 AR 2 =U 2 \uff0fI=10V\uff0f4\u00d710 -4 A=25000\u03a9=25 k\u03a9\u7531\u56fe\u4e59\u77e5\u5f53R 2 =25k\u03a9\u65f6\uff0c\u5bf9\u5e94\u7684\u6e29\u5ea6\u4e3a15\u2103 \u5f53U ab =4V\u65f6\uff1a\u7535\u963bR 1 \u4e0e\u7535\u963bR 2 \u4e32\u8054\uff0cR 2 \u4e24\u7aef\u7535\u538bU 2 =8V\u3002;I\u2019=U ab \uff0fR 1 =4V\uff0f5000\u03a9=8\u00d710 -4 AR 2 =U 2 \uff0fI\u2019=8V\uff0f8\u00d710 -4 A=10 4\u03a9 =10k\u03a9\u7531\u56fe\u4e59\u77e5\u5f53R 2 =10k \u03a9\u65f6\uff0c\u5bf9\u5e94\u7684\u6e29\u5ea6\u4e3a50\u2103
自动恒温箱原理简图：
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绛旓細鈭礗= U 1 R 0 + R 1 锛屽嵆锛0.06A= 9V R 0 +100惟 锛屸埓鐢甸樆绠盧 0 搴旀帴鍏鐢佃矾鐨勯樆鍊硷細R 0 =50惟锛涳紙3锛夎嫢瑕佹彁楂鎭掓俯绠鐨勮瀹氭俯搴︼紝鐢卞浘涔欑煡閬擄紝鐑晱鐢甸樆鐨勯樆鍊糝 1 灏嗗噺灏忥紝琛旈搧鍚稿悎宸ヤ綔鐢垫祦鍗崇嚎鍦堜腑鐨勭數娴佷粛闇60mA锛屽嵆瑕佹眰鎺у埗鐢佃矾涓殑鎬荤數闃讳笉鍙橈紝鎵...
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绛旓細锛1锛濡傚浘鎵绀锛2锛変骇鐢熺殑鐑噺锛歈=U22R0t=(220V)244惟脳100s=1.1脳105J锛涳紙3锛夊綋鐢电缁х數鍣ㄧ嚎鍦堢殑鐢垫祦杈惧埌60mA鏃讹紝璁炬鏃剁儹鏁忕數闃荤殑闃诲间负R01锛屽垯R01=U1I-R2=9V60mA-50惟=100惟锛涚敱鍥惧彲鐭ワ紝鐑晱鐢甸樆涓100惟鏃跺搴旂殑娓╁害涓50鈩冿紝鍗鎭掓俯绠鐨勬俯搴﹀皢绋冲畾鍦50鈩冿紟锛4锛変粠鍥句箼鍙煡锛岃鎻愰珮...
绛旓細锛1锛100W 锛2锛18V 430惟 璇曢鍒嗘瀽锛氾紙1锛夊綋璇鎭掓俯绠澶勪簬鍔犵儹鐘舵佹椂锛屽伐浣鐢佃矾鐨勫姛鐜囦负锛 锛2锛夊綋琛旈搧鎭板ソ琚媺璧锋椂锛屽洜涓虹嚎鍦堜笌鍙彉鐢甸樆銆佹粦鍔ㄥ彉闃诲櫒涓茶仈R 鎬 =R 绾 +R鈥+R=20惟+300惟+180惟=500惟 U=I 灏 R 鎬 =0.036A脳500惟=18V褰撹閾佹伆濂借鍚稿紩鏃讹紝婊戝姩鍙橀樆鍣ㄥ拰鍙彉鐢...
