Question

determine the current through the 300-ohm resistor, in amps.

Explanation:

Identify the circuit configuration

Using the Series and Parallel Circuits knowledge point

• The circuit consists of a single loop containing a \(1.5\text{ V}\) voltage source and three resistors: \(300\ \Omega\), \(150\ \Omega\), and \(600\ \Omega\).
• Since there are no junctions or branching paths, all components are connected in series.

Calculate the total equivalent resistance

Using the Equivalent Resistance knowledge point

$$ R_{\text{eq}} = R_1 + R_2 + R_3 = 300\ \Omega + 150\ \Omega + 600\ \Omega = 1050\ \Omega $$

Calculate the total circuit current

Using the Ohm's Law knowledge point

$$ I = \frac{V}{R_{\text{eq}}} = \frac{1.5\text{ V}}{1050\ \Omega} = \frac{1}{700}\text{ A} \approx 0.00143\text{ A} $$

Determine the current through the target resistor

Using the Series and Parallel Circuits knowledge point

• In a series circuit, the current is identical through all components.
• Therefore, the current through the \(300\ \Omega\) resistor is equal to the total current.

$$ I_{300} = I = \frac{1}{700}\text{ A} \approx 0.00143\text{ A} $$

Answer:

\(0.00143\text{ A}\) (or \(\frac{1}{700}\text{ A}\))