Fundamental Electrical and Electronic Principles, Third Edition

D.C. Circuits 33(a)(b)(c)R R 1 R 2 R 3 ohm 330 1500 470R 2300 Ω or 2.3 k Ω AnsI ER amp242300I 10.43 mA AnsV 1 IR 1 volt 10.43 10 3 330V 1 3.44 V AnsV 2 IR 2 volt 10.43 10 3 1500V 2 15.65 volts AnsV 3 IR 3 volt 10.43 10 3 470V 3 4.90 V AnsNote: The sum of the above p.d.s is 23.99 V instead of 24 V due to the roundingerrors in the calculation. It should also be noted that the value quoted for thecurrent was 10.43 mA whereas the calculator answer is 10.4347 mA. This lattervalue was then stored in the calculator memory and used in the calculations forpart (c), thus reducing the rounding errors to an acceptable minimum.(d)P EI watt 24 10.43 10 3P 0.25 W or 250 mW AnsIt should be noted that the power is dissipated by the three resistors in thecircuit. Hence, the circuit power could have been determined by calculating thepower dissipated by each of these and adding these values to give the total. Thisis shown below, and serves, as a check for the last answer.P1I 2 R1watt( 10. 43103)2330P1 35.93mWP 1 1 3 22 ( 043 . 0 ) 1500163.33mWP3( 10. 43103)2470 511. 8mWtotal power: P P1 P2P3wattso P 250.44mw(Note the worsening effect of continuous rounding error)