Advertisements
Advertisements
प्रश्न
How would the stopping potential for a given photosensitive surface change if the frequency of the incident radiation were increased? Justify your answer.
Advertisements
उत्तर
The stopping potential for a certain photosensitive surface increases as the frequency of the incident radiation increases. This is because the stopping potential is directly proportional to the frequency of the incident radiation, according to the photoelectric effect equation: Kmax = hf - Φ, where h is Planck's constant, f is the frequency of incident radiation and the metal's work function. Kmax is the photoelectron's maximal kinetic energy. As a result, as the frequency of the input radiation increases, so does the stopping potential required to stop the photoelectrons, while the kinetic energy of the photoelectrons emitted decreases.
APPEARS IN
संबंधित प्रश्न
A photon of energy hv is absorbed by a free electron of a metal with work-function hv − φ.
In an experiment on photoelectric effect, the stopping potential is measured for monochromatic light beams corresponding to different wavelengths. The data collected are as follows:-
Wavelength (nm): 350 400 450 500 550
Stopping potential (V): 1.45 1.00 0.66 0.38 0.16
Plot the stopping potential against inverse of wavelength (1/λ) on a graph paper and find (a) Planck's constant (b) the work function of the emitter and (c) the threshold wavelength.
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
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 thin target (10–2 cm square, 10–3 m thickness) of sodium, which produces a photocurrent of 100 µA when a light of intensity 100W/m2 (λ = 660 nm) falls on it. Find the probability that a photoelectron is produced when a photons strikes a sodium atom. [Take density of Na = 0.97 kg/m3].
Why it is the frequency and not the intensity of the light source that determines whether the emission of photoelectrons will occur or not? Explain.
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 :
Which three factors are varied to examine how photocurrent behaves?
Which apparatus provides monochromatic radiation for illuminating emitter plate C?
What does emitter plate C do when light falls on it?
What is used to change light frequency and study its effect on emission and electron energy?
