The emission of light by a substance due to high temperatures: white or bright-red heat. When objects such as iron placed in fire it become dull red by 700 C degree. From 700 C degree to 1500 C degree, the color shifted from red to orange and definitely yellow; by the time the iron melts. Objects higher than 1500 C degree will be seen white such as sun surface on the day, which has a temperature of about 5700 C degree. This white color is called white hot. When temperature increasing caused by energy increasing, the object emitted colored light from black body to red and yellow to bluish-white depend on energy increasing. It means hotter the object therefore more vibration energy of the atom and higher the frequency of the light in equilibrium with it.
This section has no relevant content published at this time.