Question

Part A

How much current flows through the bottom wire in the figure(Figure 1) ?

Express your answer to two significant figures and include the appropriate units.

Part B

In which direction current flows through the bottom wire in the figure?

9 V 100 6 (2 12 24 Bottom wire 15 V

Answer 1

Solution:

a) The current thru the bottom wire = I5 = 0.42 A

b) The directionof current thru the bottom wire is towards the Right

a) The current thru the bottom wire = I5 =�0.42 A b) The directionof current thru the bottom wire is towards the�Right for loop1, 9 - 6I_1 - 12 I_3 = 0 righatrrow (1) for loop 2, 15 - 10I_2 - 24I_4 = 0 rightarrow (2) for loop3, -24 I_4 + 12I_3 = 0 righatrrow (3) I_1 = I_3 + I_5 and I_4 = I_4 = I_2 + I_5 from (1), -6I_1 - 12I_5 = -9 Righatrrow 2I_1 + 4I_3 = 3 Righatrrow I_1 = 15 - 2 I_3 from (2), 15 - 10I_2 = 24I_4 Righatrrow I_2 = 1.5 - 2.4 I_4 from (3) -2I_4 = -I_3 Righatrrow I_3 = 2I_4 I_1 = I_3 + I_5 Righatrrow 1.5 - 2I_3 = I_3 + I_5 Righatrrow I_5 = 1.5 - 3I_3 Therefore 1.5 - 3I_3 = 3.4 I_4 - 1.5 Righatrrow 1.5 - 3(2II_4) = 3.4 I_4 - 1.5 Righatrrow 3.4 I_4 + 6 I_4 = 3 Righatrrow 9.4 I_4 = 3 Righatrrow I_4 = 0.32 A I_3 = 2I_4 Righatrrow I_3 = 2(0.32) = 0.64 A