Answers to Problems - Electrical Power

  1. If a 3 Ω resistor (R1) and a 5 Ω resistor (R2) are placed in series with a 10 V supply, what is the power dissipated in each resistor?


    Current  I  =  10 V  =  1.25 A
    8 Ω



    Power (R1)  =  I 2  ×  R1  =  1.5625 A  ×  3 Ω  =  4.6875 W



    Power (R2)  =  I 2  ×  R2  =  1.5625 A  ×  5 Ω  =  7.8125 W



  2. What is the power dissipated in each resistor if they are connected in parallel with the supply?


    Power (R1)  =  V 2  =  100 V  =  33.3333 W
    R13 Ω

    Power (R2)  =  V 2  =  100 V  =  20.0 W
    R25 Ω