Question Detail
Question
Which determines the number of electrons emitted by a photoelectric material?
Correct Answer
Option A is the correct answer.
Detailed Explanation
In the photoelectric effect, the number of photoelectrons emitted is directly proportional to the intensity (or brightness) of the incident light. A higher intensity means more photons are striking the metal surface per unit time, leading to more electrons being ejected, provided the frequency is above the threshold frequency. Frequency and wavelength (which is inversely related to frequency) determine whether electrons are emitted at all and their maximum kinetic energy, not the number of electrons.
Hint
Think about how many photons are hitting the surface per unit time.