Question

An electric stove burner on its highest setting exhibits an orange glow.

A) When the burner setting is changed to low, the burner continues to produce heat but the orange glow disappears. How can this observation be explained with reference to one of the fundamental observations that led to the notion of the quanta?

B) Suppose that the energy provided to the burner could be increased beyond the highest setting of the stove. What would we expect to observe with regard to visible light emitted by the burner?

Answer 1

A) Burner exhibits an orange glow on its highest setting. This indicates burner emits the energy which is in visible region. It emits the energy with the wave length equal to wave length of photons in orange region. When the burner setting is changed to low, the burner continues to produce heat but the orange glow disappears this indicates the energy of emitted radiation is less than the energy of photons in visible region. Emitted radiation may be the IR radiation which has less energy than visible radiation and IR radiation is not visible. That is why orange glow is disappeared.

B) Suppose that the energy provided to the burner could be increased beyond the highest setting of the stove. Then other colors in visible which are having greater energy may be appeared. The color which are having greater energy than orange color are yellow, Green, Blue and violet. Any one of the color may be appeared. Color appearance depends on amount of energy provided to the burner beyond the highest setting of the stove.