A Level Physics Practice Exam

How do the electrical characteristics of a light bulb differ from those of a metal wire?

1. Light bulbs have higher resistance than metal wires

2. Metal wires have higher power ratings than light bulbs

3. Light bulbs conduct electricity better than metal wires

4. Both have similar resistance values

The correct answer is: Light bulbs have higher resistance than metal wires

Light bulbs and metal wires exhibit different electrical characteristics primarily due to their construction and purpose. The correct answer highlights that light bulbs have higher resistance than metal wires. A light bulb is designed to convert electrical energy into light and heat. The filament inside a typical incandescent light bulb, for instance, is made of tungsten, which has a high resistance compared to copper, the material commonly used for metal wires. When current flows through the filament, the high resistance causes it to heat up to a point where it emits light. In contrast, metal wires are designed to conduct electricity with minimal resistance to allow for efficient power transmission. Copper has low resistance, making it suitable for this purpose. Thus, in terms of resistance characteristics, light bulbs indeed possess significantly higher resistance when compared to metal wires, which is essential for their function in converting electrical energy to light. This understanding clarifies the distinct roles and characteristics of light bulbs and metal wires in electrical circuits.