From the diagram above, calculate the total current in the circuit
Attached Figure / Diagram
A
5.0A
B
3.7A
C
4.5A
D
4.0A
Verified Correct Answer: B.
Physical Principles & Numerical Solution
V = IR from ohms law
I = \(\frac{V}{R}\)
Since the resistances are in parallel
\(\frac{1}{Reff}\) = \(\frac{1}{18}\) + \(\frac{1}{12}\) + \(\frac{1}{6}\)
= \(\frac{2 + 3 + 6}{36}\) = \(\frac{11}{36}\)
R\(_{eff}\) = \(\frac{36}{11}\) = 3.27
I = I\(_1\) + I\(_2\) + I\(_3\)
= \(\frac{V}{Reff}\)= \(\frac{12}{3.27}\)
= 3.669A
I = 3.7A
Source: Myschool Past Questions Archive (Record #46451)