The current in the 800 resistor in the drawing is 0420 A Fin

The current in the 8.00-? resistor in the drawing is 0.420 A. Find the current in (a) the 20.0-? resistor and in (b) the 9.00-? resistor.

Current through 16 ohm resistor is

2 ( 0.420 A ) = 0.84 A

current through 4 ohm resistor is

0.420 A / 4 = 0.105 A.

Thus the current throuigh 20 ohm resistor is

I = ( 0.84 ohm ) + ( 0.105 ohm ) = 0.945 ohm

voltage across 8 ohm resistor is

V = I R = ( 0.420 A ) ( 8 ohm ) = 3.36 V

Current through 9 ohm resistor is

I = V / 9 = 3.36 V / 9 ohm = 0.3733 A