1. 7. (12 points) The values of the resistors in the figure are R1 (o R2 1 2 R3 4V 6.0 Find the
current, the voltage drop, and the power dis- sipated by each resistor. Resistor-(volts) TÃ (mA)
PTW1 Ri R2
Solution
r2 and r3 are in parallel
r23 = r2*r3/r2+r3
r23= 6*12/18 = 4 ohm
r1 and r23 are in sereis
r tot = r1+r23 = 15+4 = 19 ohm
from ohms law
v = ir
i = v/r = 4/19 = 0.21 A
in a sereis combination current is same
so i1 = i23 = i = 0.21 A
v1 = i1*r1 = 0.21*15 = 3.15 V
p1 = v1*i1 = 0.66 W
v23 = 0.21*4 = 0.84 V
in a parallel combiantion voltage is same
v23 = v2 = v3 = 0.84 V

2. i2 = v2/r2 = 0.84/6 = 0.14 A
p2 = v2*i2 = 0.118 W
i3 = v3/r3 = 0.84/12 = 0.07 A
p3 = i3*v3 = 0.058 W