Answer
(a) increase
(b) decrease
(c) decrease
(d) decrease
Work Step by Step
(a) We know that the kinetic energy of the electrons is directly proportional to the frequency of light. Thus, we conclude that the kinetic energy of the electrons increases.
(b) The kinetic energy and De Broglie wavelength of the electrons are inversely proportional. That is why the minimum De Broglie wavelength of the electrons decreases with the increase in the frequency of light.
(c) We know that the number of electrons ejected per second decreases.
(d) We know that the electric current in the photo tube decreases.
