Multiple choice

A crystal capable of absorbing a radiation and re-emitting it in the form of visible light, does so after a certain small time interval of excitation. This phenomenon is called

  1. phosphorescence.

  2. fluorescence.

  3. photolysis.

  4. absorption.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation.