Which of the following is a transducer that converts electrical energy into light for general illumination?

• A. Lighting lamp
• B. Indicator lamp
• C. Motor
• D. Heater

Answer: (A)

The key idea is energy conversion: a transducer changes energy from one form to another. A lighting lamp converts electrical energy into radiant energy (light) to provide general illumination, making it the device designed to light up a space. Indicator lamp also makes light, but it’s used for signaling rather than lighting an area broadly. A motor changes electrical energy into mechanical energy to do work, and a heater turns electrical energy into heat. So the lighting lamp is the device intended for general illumination.