Question

a 50w resistor is in parallel with 100w resistor. current in 50w resistor is 7.2a. how will you add a third resistor and what will be its value if the line current is to be 12.1a​

Answer 1

Answer:

Let the two resistors be R1=100ΩR1=100Ω and R2=200ΩR2=200Ω

The voltage of power source, V =40V=40V

The total resistance of the circuit is RT=R1+R2=100+200=300ΩRT=R1+R2=100+200=300Ω

Therefore the total current flowing through the circuit is

i=VRT=40300=0.133Ai=VRT=40300=0.133A

Therefore the voltage across the two resistors is

V1=iR1=0.133×100=13.33VV1=iR1=0.133×100=13.33V

V2=V−V1=40–13.33=26.67VV2=V−V1=40–13.33=26.67V

Power delivered to the resistor R1R1 and R2R2 are

P1=V1i=13.33×0.133=1.773wattP1=V1i=13.33×0.133=1.773watt

P2=V2i=26.67×0.133=3.547wattP2=V2i=26.67×0.133=3.547watt