1、分壓與限流的研究實(shí)驗(yàn)報(bào)告【實(shí)驗(yàn)?zāi)康摹? .熟悉分壓電路和限流電流，并比較分壓電路和限流電路的性能;2 .研究滑線變阻器的有關(guān)參數(shù)；【實(shí)驗(yàn)原理】1.分壓電路如圖（1）所示，滑動(dòng)觸頭P從a移動(dòng)到b,電阻箱的電阻為R,由于調(diào)解滑動(dòng)變阻器，電路中總電阻發(fā)生變化，使電阻箱R的電壓也發(fā)生變化，即電壓表的示數(shù)有變化，設(shè)電路的電源電動(dòng)勢(shì)為E,忽略電源的內(nèi)阻，由歐姆定律可得出變阻器兩端的電壓的計(jì)算公式，推導(dǎo)過程如下：電路中總電阻為：%=-RR-+R2（1）RR根據(jù)歐姆定律得電路中總電流為：(2)(3)I二巨二一R黑R2所以在此根據(jù)歐姆定律得出電阻箱的電壓為:u=i應(yīng)=ERRRR1R(RR2)RR2又因?yàn)榛瑒?dòng)變阻

2、器的最大電阻為Ro=R-R2帶入（3）式，并化簡(jiǎn)可得:ERR2R0R1-RRq-R1(4)設(shè)XY奢(5)RoRo聯(lián)立（4）、（5）,消去R,R,可得:XYE2XY-Y2所以:UXY二二2EXY-Y2(6)(7)由式（7）可知，當(dāng)X一定時(shí)，U/E與Y值存在一定的函數(shù)關(guān)系，可以多測(cè)幾組數(shù)據(jù)，得出函數(shù)圖像，分析分壓電路的性能。2.限流電路如圖2所示，滑動(dòng)觸頭P移動(dòng)到a,負(fù)載電阻R上的電壓最大，為電源電壓E,相應(yīng)的電流此時(shí)也是最大的，由歐姆定律可得此時(shí)電路中的最大電流為：Imax=H（8）R在滑動(dòng)觸頭不在a或者b位置時(shí)，電路中的電流大小為：(9)聯(lián)立式（5）、（8）、（9）,消去E,R,R,并化簡(jiǎn)整理

3、可得:IXImax-XY(10)由（10）式可彳為當(dāng)X一定時(shí)，I/Imax與Y值存在一定的函數(shù)關(guān)系，同樣,多測(cè)幾組數(shù)據(jù)，畫出兩者的函數(shù)圖象，分析限流電路的性能。圖2【實(shí)驗(yàn)儀器】穩(wěn)壓電源、電流表、電壓表、滑動(dòng)變阻器R0(03700Q)、變阻箱R(099999Q)、開關(guān)、導(dǎo)線【實(shí)驗(yàn)步驟】一、分壓電路性能的研究1 .找到所用的實(shí)驗(yàn)器材，并檢查是否損壞；2 .按圖(1)所示電路圖連接好電路，打開穩(wěn)壓電源開關(guān)，并調(diào)節(jié)使電源電壓E為3V3 .選擇不同的X值，并根據(jù)不同的X值選擇好變阻箱的阻值，然后設(shè)計(jì)實(shí)驗(yàn)數(shù)據(jù)表格1,以便記錄數(shù)據(jù)；4 .撥動(dòng)滑動(dòng)變阻器的滑動(dòng)觸頭P,分別置于不同的位置，從而確定好Y值；5 .

4、讀取并記錄每次位置的電壓值；6 .實(shí)驗(yàn)結(jié)束后，將不用到的儀器歸回原位置。二、限流電路性能的研究1 .按圖(1)所示電路圖連接好電路，打開穩(wěn)壓電源開關(guān)，并調(diào)節(jié)使電源電壓E為4V2 .選擇不同的X值，并根據(jù)不同的X值選擇好變阻箱的阻值，然后設(shè)計(jì)實(shí)驗(yàn)數(shù)據(jù)表格2,以便記錄數(shù)據(jù)；3 .撥動(dòng)滑動(dòng)變阻器的滑動(dòng)觸頭P,分別置于不同的位置，從而確定好Y值；4 .讀取并記錄每次位置的電流值；5 .實(shí)驗(yàn)結(jié)束后，將不用到的儀器歸回原位置。五實(shí)驗(yàn)數(shù)據(jù)及處理一、分壓電路性能的研究E=3M電壓表白量程為03V（1）X=0.01（滑動(dòng)變阻器R=3700Q,變阻箱R=37Q）Y0.0000.1000.2000.3000.400

5、0.5000.6000.7000.8000.9001.000U(v)0.0000.0100.0260.0300.0440.0500.0700.1000.2222.9263.000U/E0.0000.0030.0090.0100.0150.0170.0230.0330.0740.9751.000(2)X=0.1(滑動(dòng)變阻器R=3700Q,變阻箱R=370Q)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0200.1100.1440.1820.2460.3120.4500.7982.9343.000U/E0.0

6、000.0070.0370.0480.0610.0820.1040.1500.2660.9781.000(3)X=0.5(滑動(dòng)變阻器R=3700Q,變阻箱R=185g)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0500.1520.2180.5540.7501.0001.3001.8522.9463.000U/E0.0000.0170.0510.0730.1850.2500.3330.4330.6170.9821.000（4）X=1（滑動(dòng)變阻器R=3700Q,變阻箱R=370（n）Y0.0000.1000

7、.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0520.3040.5020.6520.8001.1241.4061.9242.9583.000U/E0.0000.0170.1010.1670.2170.2670.3750.4690.6410.9861.000(5)X=2(滑動(dòng)變阻器R=3700Q,變阻箱R=7400Q)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0250.3260.5260.7080.8561.1001.4561.9542.9

8、603.000U/E0.0000.0080.1090.1750.2360.2850.3670.4850.6510.9871.000(6)X=4(滑動(dòng)變阻器R=3700Q,變阻箱R=1480CQ)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0520.3520.5540.7520.9561.2241.6362.1522.9723.000U/E0.0000.0170.1170.1850.2510.3190.4080.5450.7170.9911.000(7)X=10(滑動(dòng)變阻器R=3700Q,變阻箱R=3700

9、CD)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000U(v)0.0000.0540.3320.5540.7020.9461.2001.5662.0522.9683.000U/E0.0000.0180.1110.1850.2340.3150.4000.5220.6840.9891.000U/E與Y的關(guān)系作圖，如下所示:分壓電路性能研究圖-B-U/匚-*-YT-U/EYT-U/E-1-¥U/EY一-U/E-Yr-u/EU/L二、限流電路的研究E=4.0V(1)X=0.01(滑動(dòng)變阻器R=3700Q,變阻箱R=37Q)Y0.

10、0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(mA103.00050.5006.8004.0002.6002.0001.6201.4001.2000.9201.0001.0000.4900.0660.0790.3820.5000.6230.7000.7410.6570.833(2)X=0.1(滑動(dòng)變阻器R=3700Q,變阻箱R=370Q)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(mA10.8009.2504.4003.0002.2001.8001.6001.

11、2001.1500.8801.0001.0000.8560.4760.6820.7330.8180.8890.7500.9580.7651.136(3)X=0.5(滑動(dòng)變阻器R=3700Q,變阻箱R=185g)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(A)2.1552.1001.6521.4251.2051.0500.9500.8500.8000.6800.7001.0000.9740.7870.8630.8460.8710.9050.8950.9410.8501.029（4）X=1（滑動(dòng)變阻器R=3700Q,變阻箱R=

12、370（n）Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(A)1.1001.0500.9500.8500.8000.7000.6590.6250.5990.5000.5501.0000.9550.9050.8950.9410.8750.9410.9480.9580.8351.100(5)X=2(滑動(dòng)變阻器R=3700Q,變阻箱R=740g)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(A)0.5800.5500.5000.4550.4500.4250.40

13、00.3590.3550.3500.3501.0000.9480.9090.9100.9890.9440.9410.8980.9890.9861.000(6)X=4(滑動(dòng)變阻器R=3700Q,變阻箱R=1480QQ)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(A)0.2650.2600.2550.2500.2490.2470.2450.2400.2350.2250.2251.0000.9810.9810.9800.9960.9920.9920.9800.9790.9571.000(7)X=10(滑動(dòng)變阻器R=3700Q,變

14、阻箱R=3700CQ)Y0.0000.1000.2000.3000.4000.5000.6000.7000.8000.9001.000I(A)0.1300.1250.1200.1150.1100.1050.1000.1000.1000.1000.1001.0000.9620.9600.9580.9570.9550.9521.0001.0001.0001.000l/lmax限流電路性能研究/ImaxAl/lmaxYl/lmaxtl/lmaxYl/lmax-Y-l/lmax-A-Y-l/lmax【思考與討論】分壓電路和限流電路性能的分析1 .分壓電路中，要使電壓從0到V0整個(gè)范圍均勻變化，取x>1比較合適，因此要選用的滑動(dòng)變阻器小于負(fù)載電阻R;2 .做分