Question

When several resistors are connected in parallel in a circuit, what happens to the current and the equivalent resistance?

• A. Current divides among resistors, equivalent resistance decreases.
• B. Current remains the same, equivalent resistance increases.
• C. Current divides among resistors, equivalent resistance increases.
• D. Current remains the same, equivalent resistance remains the same.

Hint:

Adding a resistor in parallel always decreases the equivalent resistance of the circuit.
This is analogous to opening more lanes on a highway, which reduces the overall traffic resistance.

Answer 1

The Correct Option is A

Step 1: Picture a parallel circuit.
In parallel, every resistor is connected across the same two points, so each one feels the same voltage \(V\), but they don't have to share the same current.
Step 2: Follow the current.
Current flowing in from the source splits at the junction and takes several paths, one through each resistor, so \[ I = I_1 + I_2 + \dots + I_n \] that is what we mean by the current dividing.
Step 3: Work out what this does to resistance.
Adding another resistor in parallel opens up one more path for charge to flow, so the combination as a whole finds it easier to pass current. This is captured by \[ \frac{1}{R_{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + \dots \] and since the right side grows as we add terms, \(R_{eq}\) itself must shrink below the smallest individual resistance.
\[ \boxed{\text{Current divides among resistors, equivalent resistance decreases}} \]