Answer:
Option C. 4.5 A
Explanation:
We'll begin by calculating the equivalent resistance of R1 and R3. This can be obtained as follow:
R1 = 6 Ω
R3 = 3 Ω
Equivalent of R1 and R3 =?
Since R1 and R3 are in parallel connections, we shall their equivalence as follow:
Equivalent of R1 and R3 = (R1×R3) /(R1 + R3)
Equivalent of R1 and R3 = (6×3)/(6+3)
Equivalent of R1 and R3 = 18/9
Equivalent of R1 and R3 = 2 Ω
Next, we shall determine the equivalent resistance in the circuit.
This is illustrated below:
R2 = 2 Ω
Equivalent of R1 and R3 = 2 Ω
Equivalent resistance (R) in the circuit =?
Note: Equivalent of R1 and R3 is in series connection with R2.
Equivalent Resistance (R) = (Equivalent of R1 and R3) + R2
Equivalent Resistance (R) = 2 + 2
Equivalent Resistance (R) = 4 Ω
Finally, we shall determine the total current in the circuit as follow:
Potential difference (V) = 18 V
Equivalent Resistance (R) = 4 Ω
Current (I) =.?
From ohm's:
V = IR
Where V is the potential difference.
I is the current.
R is the resistance.
V = IR
18 = I × 4
Divide both side by 4
I = 18/4
I = 4.5 A
Therefore, the total current in the circuit is 4.5 A.
