(20 13? Nanning) In the circuit shown in the figure, the known resistance is R 1: r2 = 1: 3. If meters A and B are voltmeters, when switch S is closed, r 1 and R.

(1) As can be seen from the circuit diagram, when both meter A and meter B are voltmeters, two resistors are connected in series, one voltmeter is used to measure the voltage across R 1, and meter B measures the voltage of the power supply.

∫ The total voltage in the series circuit is equal to the sum of the divided voltages, and the currents everywhere are equal.

According to ohm's law:

U A U B = U 1U = U 1U 1+U2 = IR 1ir 1+IR2 = r 1r 1+R2 = r 1r 1+3r 65438。

(2) Both A and B meters are ammeters. When the switch S is turned off, the two resistors are connected in parallel. A ammeter measures the main current, and B ammeter measures the R 1 branch current.

∫ The voltages at both ends of each branch in the parallel circuit are equal,

∴ The currents of the two tributaries are:

I 1=UR 1，I2=UR2，

The main current in the parallel circuit is equal to the sum of the currents of each branch,

∴ Iaib = I1+I2i1= ur1+Ur2ur1= ur1+U3R1u I praised it and stepped on it. What's your comment on this answer? Put away comments//high quality or satisfaction or special types or recommended answers dottimewindow.iperformance & window.iperformance.mark ('c _ best',+newdate); Lawyer recommendation service: If your problem has not been solved, please describe your problem in detail and provide free professional consultation through Baidu Law Professional Edition. Other similar problems 2012-11-10. In the circuit shown in the figure, the resistance is r1= R2 = R3 =10Ω. When switches S 1 and S2 are closed, 222017-12-16 (2014? Panjin simulation) In the circuit shown in the figure, the known resistance is r 1: R2 = 1: 3. If meters A and B are voltmeter, R220 13-06-0 1 when switch S is closed. In the circuit shown in Figure 7, the resistance of R2 is 3 Ω. After the switch is closed, the voltmeter indicates 6V and the ammeter indicates 1A, then R1= _ _ ω 32012-12-30 In the circuit shown, the resistance R1= R2 = R3 = 65430. When switches S 1 and S2 are closed, 62016-12-01(2013? Nanning) In the circuit diagram shown in the figure, the resistance value of the resistor R 1 is 10ω. When the switch S is closed, the indication of is 0.4A, and the indication of is 0.6a. It is found that: (220 13-02- 13) In the circuit shown in the figure, the resistance of R2 is 3 Ω. When the switch is closed. Then R 1=220 16-02-06 In the circuit shown in the figure, the voltage between A and B remains constant, and R1and R2 are constant resistances. If the switch S is closed, the ammeter is connected to A and B, which means 420 17- 12. As shown in the figure, the resistance R 1: R2 = 3: 2. After the switch S is closed, the voltage ratio of r 1 and R2 is U1:U2 = _ _ _ _: ammeter A 1 and A2' s 5 recommended for you: F. Context ('CMS! [{ ' URL ':'/d 0 1373 f 082025 AAF 5 1 1aa 256 e 9 edab 64034 f 1a 07？ x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto '， ' contractId':'A24KA00562 '，}，{ ' URL ':/builder/bjh-activity/articlesTask？ taskId = 1598082 & aside = 0 & footer = true & from = 0 '，' src ':'/203 FB 80 e 7 bec 54 e 773 ea 0680 ab 389 b 504 fc 26 a2d？ x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto '，' contractId ':' '，}，{ ' URL ':/s？ word = % E6 % AC % A7 % E6 % B4 % B2 % E6 % 9D % AF & sa = searchpromo _ ozb _ zhidao _ tuijian '，' src ':'/3 BF 33 a 87 e 950352 AAF 5 df 4954 143 fbf2b 2 1 18 b6b？ x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto '，' contractId ':' '，}])； Why is the cost of cancer treatment getting higher and higher? The price of electric cars has dropped many times. Is the quality guaranteed? What impact will the "network toilet" have? Is Huaqiang North's second-hand mobile phone reliable? I recommend f.context ('recbrand', [{"img": "\/86D6277F9E2F07083523F69DFB 24B 899A901F20d? x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto "，" url":"/hm.js？ 6859 ce 5a af 00 FB 00387 e 6434 E4 FCC 925 "； var s = document . getelementsbytagname(" script ")[0]； s.parentNode.insertBefore(hm，s)； })(); window . TT = 1720697853；