Answer:
The after the light changes to more energetic Violet light
Step-by-step explanation:
This type of thermometer is called a pyrometer, the light from the bulb is facing the light received from the hot object by moving the knob to the right for more current through the filament and the light changes towards more energy, violet. When the intensity from the hot source and the deserter are the same, the radiation is absorbed and the device is black, at this time the temperature is read.
The after the light changes to more energetic Violet light