Question

A 32.0 resistor is connected in parallel to a 18.0 resistor. These are joined in series to a 3.0 resistor and a source with a potential difference of 30.0 V.

(c) Calculate the current in each resistor.

A (32.0 resistor)

A (18.0 resistor)

Calculate the potential difference across each resistor.

V (32.0 resistor)
V (18.0 resistor)

Answer 1

total R=3+18*32/(50)=3+11.52=14.52
total I=30/14.52
current in 32ohm= V/32=(30/14.52) (11.42)/32
current in 18 ohm=V/32=(30/14.52)(11.42)/18
Vparallel=(30/14.52)(11.42)

Answer 2

for the 32 and 18 in parallel
1/R = 1/32 + 1/18 ----> R = 11.5
total Resistance = 11.5 + 3 = 14.5
total i = 30/14.5 = 2.07 amps
so
i through 3 ohms = 2.07
so V drop over 3 ohms = 2.07*3 = 6.14 volts
so V drop over two in parallel = 30-6.14
= 23.9 volts
so current through 32 = 23.9/32 = 0.747amp
through 18 = 23.9/18 = 1.33 amp