Question

why stopping potential changes with frequency of light but not increases with intencity of light?​

Answer 1

Answer:

Explanation:

In an experimental arrangement similar to that of the cathode ray tube, scientists had observed another phenomenon. In contrast to the cathode ray tube, the cathode was not heated nor were large bias potentials used. Instead, it was found that when light impinged upon the surface of the cathode, electrons could be ejected from the cathode and picked up by the anode - a current could be measured. If an opposing bias voltage was established, a certain threshold potential was found above which no current would be measured. This was called the stopping voltage. It was determined that the stopping voltage was different when the cathode was made from different materials. But what was particularly troubling was the effect observed when the wavelength and intensity of the light which struck the surface were changed. The stopping potential did not change when the intensity of the light was changed. The current, however, did increase with increasing incident light intensity. The stopping potential increased when the wavelength of the incident light decreased. Furthermore, as the light intensity decreased, the current also dropped - nevertheless the onset of the current from the time the light first hit the surface was always instantaneous.