Standard Science Primary 5 Systems

Study the circuit diagram. Switch S1 is closed and Switch S2 is open. What will be the state of Bulb B1?

A It will be lit brightly.
B It will not be lit.
C It will be lit dimly.
D It will flash.
Show Worked Solution

Worked Solution

Step 1: The circuit is a series circuit with two switches. Step 2: For current to flow in a series circuit, the entire path must be closed. Step 3: Because Switch S2 is open, there is a gap in the circuit. Step 4: Therefore, current cannot flow, and Bulb B1 will not light up.

Correct answer: It will not be lit.

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