Question

Question 1.. Light of frequency 1.9 times the threshold frequency is incident on
a photosensitive material. If the frequency is halved and intensity is doubled,
the photocurrent becomes
(a) quadrupled
(b) doubled
(c) halved
(d) zero​

Answer 1

Answer:

option d

Explanation:

since photocurrent is directly proportional to number of electrons emitted , increasing intensity will definitely increase the no of electrons being ejected thus increasing current . but it is also necessary that incidentfrequency should be greater than threshold Freq. but if frequency is halved.. then new incident frequency becomes 0.95 times threshold frequency which is lesser (0.95f<1f).. then no photoelectric effect takes place

Answer 2

Light of frequency 1.9 times the threshold frequency is incident on  a photosensitive material. If the frequency is halved and intensity is doubled, the photocurrent becomes (d) zero​

Explanation:

• No photoelectric emission happens when the frequency of incoming radiation falls below a specific threshold. As a consequence, halting potential involvement is prevented.
• The colour of halting potential reaches zero when the frequency of incoming radiation matches the frequency of stopping potential.
• Light with a frequency equal to the threshold frequency will eject the electron without releasing any kinetic energy. If the frequency of light surpasses a certain threshold, the electron is expelled, releasing kinetic energy.