Automotive Electronics Practice Test

What happens to the current in a parallel circuit if one branch is opened (bulb removed)?

1. Current stops

2. It decreases across other branches

3. It remains unchanged for other branches

4. It doubles

The correct answer is: It remains unchanged for other branches

When one branch of a parallel circuit is opened, the remaining branches will continue to function normally. In a parallel configuration, the voltage across all components is the same, and each branch operates independently of the others. Therefore, when a bulb is removed, the current in that specific branch does stop, but the current flowing through the other branches will remain unchanged. Each remaining branch can still draw current based on its own resistance, and since the voltage across those branches remains constant, their current will not be impacted by the removal of one branch. Thus, the overall behavior of the circuit illustrates that despite a change in one part, the other paths maintain the same current flow.