Question

A four-resistor circuit is shown in the figure. The values of the resistors are as follows: Ri=10 Ohms, Rz=R3=6 Ohms, R4=2 Ohms. What is the equivalent resistance Reg for this circuit? R M R3 R3 R3 > O 0.50 ohms O 2.00 ohms 0 3.33 ohms 0 5.25 ohms o 7.50 ohms Question 8 5 pts The circuit shown in the figure below contains three resistors (R1, R2, and R3) and three batteries (VA. VB, and Vc). The resistor values are: R1-2 Ohms, R2=R3-4 Ohms, and the battery voltages are VA-25 V. V8-15 V, and Vc-20 V. When the circuit is connected, what will be the power dissipated by R3? VC R VA V. R RE O 1.25 W O 20W Oo oo O 5.0 W O 6.25 W 08.13 W

Answer 1

R4 O. Equivalent resistance of parallel combination of R2 and R3 is, $ I el Rea Rei 1 / 2 R2 RE R2 1 Ri= lor, R2 = R₂=6l, R4=an oh Roi- 4 2 1 1 e 1 6 1/ » Rpiros R4 R Roi si Rp1= 32 Hence equivalent coke't is drawn ons equivalent resistance of series combination of Ra and Rp. is, Rsi = Rauppi & Rs1= (2+3) af Rsi : 52 Hence equivalent oicunt is draws as equivalent resistance of parallel combination Ri and Rsi is, Regal I 1 Rsi RI Ri Rs) Rea - Req= s 1 1 10 24 Req = 10 3 =) : 3. 331 Req= 5. Equivalent sexistance of corca't is 3.331 opticle 6, ie, 3.334 is carorect solution

O. P I Vc 4 R Ug VA R2 b a R3 VA: 25V, VA = 15 V, Vc= 200, Ris 21, R2= R3=412 Let cop astume catherst I to flow in direction shown equivalent resistance of parallel combination of R2 and R3 is, 1 1 a LI ay olen Rp R2 Rp= 1 - 1 R2 R3 => RP = 42 2 1 RP- of 1 4 ¢ Vc = Rp=an I R applying VA b 4 Hence circuit is bous asa KUL in closed loop, VB + VC - IR, -VA-IRP=0 - I Crie RPDa Vee Vc - VA Rp => I = VB + Vc- VA qua RIA RP => I = 65+20-25 ) A => I: 10, A => I: 2.5 A (2+2) :. Vab= Ib Rp => Vab= (2.562)" =) Vab=5v .. power dissipated across R3, Pz - Vab? » P3 : 52W Ra MP3: 6.25 W Hence power dissipated by R3 is 6.25w leption 4) 4