Question

Figure 1(a) shows a combination of series and parallel circuit while Table 1 lists the colour code of 4-band resistor. The voltage source, vs is indicated in Figure 1(b). (a) Find the nominal value of resistor Rand the range of its actual resistance. (2 marks) (b) Using the nominal value of RL, compute the effective voltage across Rt. (6 marks) (c) Using the nominal value of Ru, calculate the average power dissipated in RL. (2 marks) 350 22 ş 150 Ω blue black brown gold 500 22 RL Vs 2 kΩ ş 500 S2 5002 (a) V (V) 4 2 موالي t(s) 3 4 -2 (b) Figure Q1 Resistance value Colour Black Brown Red Orange Table 1 Digit 0 1 2 3 4 5 6 7 8 9 +5% +10% Yellow Green Blue Violet Grey White Gold Silver Tolerance

Answer 1

Solution 35062 150. M 500s RL gka ب00 Vs 577 5 Step-11 Equivalent resistanu calculation of Complex resisti've betworis. 350 150 mm 350-tihe 150. 500m a 500€ 500 mm 500m akm 500m Qkm muha 5002 ba b. series and applying → Reduce the circuit by parallel equivalance. a a 250.00 2000 m 2000.c. 500 - 2500 b A. Rab 2000 * 500 2000 +500 2000 x 500 2560 = 400. step-21 BL calculation from color code. Holol. Brown Blue Blacs +5% 6 X101 1 0 xion RLE 60 X10' 75% ohm RL = 600 + 5% of Lay Nominal rame of RL = 600 ohm. & range 600 £5% RL is 600 t 5 1600 100 = 600 + 30 i range of Re is of RL is 630 to 520 ohm

Lüx The simplified cirwit of the given circuit o's RL + VL Rad = 400m Vs :: Vottage RL aeross RL is VLE x VS RL+Rab y Vs → VL = 600 600+400 → VL = 0.6 VS Vs 2 0 112 3 + 5 >tlinsee) -2 stren u VL 2.4 1.2 + 10 - 2 3 4 5 tlinsee) -12 c Average power dissipated in Rh is PL = [v.coms)? RL every 3 sec. Here, the waveform VL is repeated at so tême period (t) = 3 see. VLE ; 1?t=2 To 3 see, 1.2 ; 217? 3. 2.4 0 Lt ļ1 1.2 V (Rms) = VE fo) (VL) ² dt

11 V*[iboruto fenose poveru 3 = \ /5.76(+)' + 1.44 (t)} + 1.44 (t)} 1 [15:57 }[5.76 +1.44 +1.44 v 8064 - V 2088 oli 697 vots. 3 RL is : Average power dissipated in PL - VLC sms oms)) 2 RL 600 2.88 600 -3 = 4.8 x 10 woth x1013 PL= 408 mwath

(a) Nominal value of RL=600 ohm and range of RL is 570-630 ohm

(b) Voltage across resistor RL is VL=0.6Vs

(c) Resistor is a voltage stiff load so average power dissipated across resistor is Vrms^2 /R or (Irms^2) *RSo average power dissipated in resistor RL is PL=VLrms^2 /RL =4.8 mWatt