The frequency and the intensity of a beam of light falling on the surf...
Explanation:
Introduction:
The photoelectric effect is the phenomenon in which electrons are emitted from a material when light of certain frequency and intensity falls on its surface. The maximum kinetic energy of the emitted electrons depends on the frequency and intensity of the incident light. In this question, we are asked to determine the effect of increasing the frequency and intensity of the incident light on the maximum kinetic energy of the photoelectrons and the photoelectric current produced.
Effect of increasing the frequency:
When the frequency of the incident light is increased, the energy of each photon of light also increases. According to the photoelectric effect, electrons can only be emitted from the material if the energy of the incident photons is greater than the work function of the material. The work function is the minimum energy required to remove an electron from the material. Therefore, increasing the frequency of the incident light increases the energy of the photons and hence the maximum kinetic energy of the emitted electrons.
Effect of increasing the intensity:
Increasing the intensity of the incident light means that more photons are incident on the material per unit time. The number of photons incident per unit time is directly proportional to the intensity of the light. Therefore, increasing the intensity of the light increases the number of photons incident on the material, which in turn increases the number of photoelectrons emitted per unit time. This leads to an increase in the photoelectric current.
Combined effect:
When both the frequency and intensity of the incident light are increased by a factor of two, the maximum kinetic energy of the emitted electrons is increased by a factor greater than two. This is because both the frequency and intensity contribute to the energy of the incident photons. Therefore, the total energy of the incident photons is increased by a factor greater than two, leading to an increase in the maximum kinetic energy of the photoelectrons.
At the same time, the photoelectric current is also increased by a factor of two because the increased intensity of the light leads to a greater number of photoelectrons being emitted per unit time.
Therefore, the correct answer is option C: Increase the maximum energy of the photoelectrons by a factor greater than two, and the photoelectric current by a factor of two.