Two types of system I can think of:
A speaker.
A laser is a device that produces a thin stream of light of just a few close wavelengths.
A battery is a device that stores and produces electrical energy by converting chemical energy into electrical energy through electrochemical reactions.
A device that breaks light into colors and produces an image is a spectrophotometer or a spectrometer. These instruments measure the intensity of light as a function of its color or wavelength.
an electromagnet
a monitor
A speaker.
A printer is a device that produces soft copies of digital documents by transferring text and images from a computer onto paper.
The name of the device that produces coherent light is LASER.
The name of the device that produces coherent light is LASER.
A heater?
A laser is a device that produces a thin stream of light of just a few close wavelengths.
A battery is a device that stores and produces electrical energy by converting chemical energy into electrical energy through electrochemical reactions.
anything that has an arm
A dynamo
Geiger Counter
Mini wind turbine