Resisitors

[soso]

Determine V1 and R3 if R1= 8ohms I1= 0.75A, R2=5 Ohms and I2=6A. Note that R2 and R3 are connected in parallel. Thank you.

[Kurdt]

V1 you can calculate by using V=IR on the first resistor which turns out to be 54V (remember I is the sum of both I1 and I2 as current is split between two components in series and we can treat the parallel system to be a series entity). Secondly taking into account the fact that V is then split in parallel but current is not we can work out R2 has a potential difference across it of 30V leaving 24V across R3 which has I3=6A. Thus R3=4 Ohms.