Question

A circuit in a home provides power to a light fixture. The homeowners want to use a compact fluorescent bulb instead of an incandescent bulb. Compact fluorescent bulbs can produce as much light as incandescent bulbs but with less energy. How is this possible? a. Fluorescent bulbs produce other forms of energy, too, including heat. b. Energy is destroyed when it passes through an incandescent bulb. c. Fluorescent bulbs have been designed to put out more energy than they receive. d. Incandescent bulbs produce other forms of energy, too, including heat.

Answer 1

d.

Incandescent bulbs make light by heating a filament, so most of the electrical energy is radiated as infrared (heat) rather than visible light. Compact fluorescents produce light via a gas discharge and phosphors, converting a larger fraction of the input energy into visible light and wasting less as heat, so they give the same visible output with less energy.