Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

How does a parallel circuit differ from a series circuit?

1. It has one path for electrons

2. It has multiple paths for electrons

3. It cannot be closed

4. It uses more voltage

The correct answer is: It has multiple paths for electrons

A parallel circuit is characterized by having multiple paths for electrons to flow. This means that in a parallel configuration, each component is connected directly to the power source, allowing electricity to take different routes through the circuit. If one pathway or component fails (like a bulb burning out), the other pathways remain functional, enabling the remainder of the circuit to continue operating. This is in contrast to a series circuit, which has a single pathway for the current. In a series setup, if one component fails, the entire circuit is interrupted, and no current flows. This property of multiple paths in a parallel circuit also allows for a greater total current for the same voltage, as each parallel branch can carry its own load. In regard to the other options: a series circuit operates with a single path for electrons, meaning if one component fails, the circuit is not complete. A parallel circuit can certainly be closed, as long as there is a complete path for electrons to travel; it's the structure that allows for multiple complete paths. Finally, while voltage can vary in different circuits depending on the configuration and the components used, a parallel circuit does not inherently "use more voltage." Instead, all branches will have the same voltage across them equal to the supply voltage.