Advanced Science Primary 5 Systems

Tim added three more batteries in series to his circuit. Suddenly, the bulb flashed brightly and then went out. Why?

A The filament in the bulb melted due to too much current.
B The bulb became an insulator.
C The wires became too hot to conduct electricity.
D The batteries ran out of energy instantly.
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Worked Solution

Step 1: Adding batteries in series increases the total voltage and current. Step 2: Every bulb has a limit to the amount of current it can handle. Step 3: Excessive current produces too much heat, causing the tungsten filament to melt (fuse).

Correct answer: The filament in the bulb melted due to too much current.

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