Advertisements
Advertisements
Question
- Assertion (A): For the radiation of a frequency greater than the threshold frequency, the photoelectric current is proportional to the intensity of the radiation.
- Reason (R): Greater the number of energy quanta available, the greater the number of electrons absorbing the energy quanta and the greater the number of electrons coming out of the metal.
Options
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
If Assertion is true but Reason is false.
If both Assertion and Reason are false.
Solution
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
Explanation:
When the frequency of the incident radiation exceeds the threshold frequency, the photoelectric current is proportional to the intensity of the radiation. As a result, the assertion is correct. As the intensity rises, so does the number of energy quanta accessible. By absorbing more energy quanta, a bigger number of electrons are emitted. A higher number of electrons equals a higher current. As a result, the photoelectric current becomes proportional to radiation intensity. So, the reason is also true, and it adequately explains the assumption.
APPEARS IN
RELATED QUESTIONS
Use the same formula you employ in (a) to obtain electron speed for an collector potential of 10 MV. Do you see what is wrong? In what way is the formula to be modified?
Monochromatic radiation of wavelength 640.2 nm (1 nm = 10−9 m) from a neon lamp irradiates photosensitive material made of caesium on tungsten. The stopping voltage is measured to be 0.54 V. The source is replaced by an iron source and its 427.2 nm line irradiates the same photo-cell. Predict the new stopping voltage.
Light of intensity 10−5 W m−2 falls on a sodium photo-cell of surface area 2 cm2. Assuming that the top 5 layers of sodium absorb the incident energy, estimate time required for photoelectric emission in the wave-picture of radiation. The work function for the metal is given to be about 2 eV. What is the implication of your answer?
Is it always true that for two sources of equal intensity, the number of photons emitted in a given time are equal?
The work function of a metal is hv0. Light of frequency v falls on this metal. Photoelectric effect will take place only if
Light of wavelength λ falls on a metal with work-function hc/λ0. Photoelectric effect will take place only if
In which of the following situations, the heavier of the two particles has smaller de Broglie wavelength? The two particles
(a) move with the same speed
(b) move with the same linear momentum
(c) move with the same kinetic energy
(d) have fallen through the same height
Define the terms "stopping potential' and 'threshold frequency' in relation to the photoelectric effect. How does one determine these physical quantities using Einstein's equation?
Consider a metal exposed to light of wavelength 600 nm. The maximum energy of the electron doubles when light of wavelength 400 nm is used. Find the work function in eV.
If photons of ultraviolet light of energy 12 eV are incident on a metal surface of work function of 4 eV, then the stopping potential (in eV) will be :
