Introduction
Photo effect discovered in 1887 by German physicist H. Hertz. At that time, it was revealed electron, and it became clear that the photo effect (specifically, external photo effect) is the electron extraction of substances when exposed to light.
The photoelectric effect or photo ionization is the emission of electrons or other free carriers when light is shone onto a material. Electrons emitted in this manner can be called photo electrons. The phenomenon is commonly studied in electronic physics, as well as in fields of chemistry, such as quantum chemistry or electrochemistry.
According to classical electromagnetic theory, this effect can be attributed to the transfer of energy from the light to an electron. From this perspective, an alteration in the intensity of light would induce changes in the kinetic energy of the electrons emitted from the metal. Furthermore, according to this theory, a sufficiently dim light would be expected to show a time lag between the initial shining of its light and the subsequent emission of an electron. However, the experimental results did not correlate with either of the two predictions made by classical theory.
Task
Watch the video and read 8 statements about the topic in the video material and decide whether the statement is "Correct" or "Incorrect", if the statement is "Incorrect", then rewrite the statement correctly.
Process
1. Photo effect discovered in 1887.
2. Electrons emitted in this manner can be called photo electrons.
3. Electron output work is a material characteristic parameter.
4. In 1887, Heinrich Hertz discovered that electrodes illuminated with ultraviolet light create electric sparks more easily.
5. The time lag between the incidence of radiation and the emission of a photoelectron is very small, less than 10−9 second.
6. The direction of distribution of emitted electrons peaks in the direction of polarization (the direction of the electric field) of the incident light, if it is linearly polarized.
Evaluation
1. Photo effect discovered in 1887. T
2. Electrons emitted in this manner can be called photo electrons. T
3. Electron output work is not a material characteristic parameter. F
4. In 1887, Heinrich Hertz discovered that electrodes illuminated with ultraviolet light create electric sparks more easily. F
5. The time lag between the incidence of radiation and the emission of a photoelectron is very small, less than 10−9 second. T
6. The direction of distribution of emitted electrons peaks in the direction of polarization (the direction of the electric field) of the incident light, if it is linearly polarized.
Conclusion
Thank you for answering questions!