Advertisements
Advertisements
प्रश्न
Find the wave number of a photon having energy of 2.072 eV
Given : Charge on electron = 1.6 x 10-19 C,
Velocity of light in air = 3 x 108 m/s,
Planck’s constant = 6.63 x 10-34 J-s.
Advertisements
उत्तर
E = hv
`:.v=E/h`
`v=C/lambda`
∴ Wave number
`1/lambda=v/c`
`=E/(hc)`
`=(2.072xx1.6xx10^(-19))/(6.63xx10^(-34)xx3xx10^8`
`=1/lambda=1.667xx10^6m^(-1)`
APPEARS IN
संबंधित प्रश्न
The momentum of a photon of de Broglie wavelength 5000Å is _______.
[Planck’s constant = 6.63 x10-34 J.s.]
Define (i) stopping potential and (ii) threshold frequency, using Einstein’s equation and drawing necessary plot between relevant quantities.
A proton and a deuteron are accelerated through the same accelerating potential. Which one of the two has less momentum?
Give reasons to justify your answer.
Write its S.I. unit of (intensity of radiation)
Radiation of frequency 1015 Hz is incident on two photosensitive surface P and Q. There is no photoemission from surface P. Photoemission occurs from surface Q but photoelectrons have zero kinetic energy. Explain these observations and find the value of work function for surface Q.
With reference to the photoelectric effect, define threshold wavelength
Write the basic features of photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based.
Write Einstein’s photoelectric equation.
According to Einstein’s model minimum energy needed for the electron to escape from a metal surface having work function ϕ0, the electron is emitted with maximum kinetic energy, Kmax = ______.
According to the Einstein’s model, stopping potential Vo for a metal having work function ϕ0 is given by ______.
Which of the following graphs correctly represents the variation of maximum kinetic energy (Ek) of photoelectrons with the frequency (𝜈) of the incident radiation?
Calculate the maximum kinetic energy of photoelectrons emitted by a metal (work function = 1.5 eV) when it is illuminated with light of wavelength 198 nm.
Plot a labelled graph of |Vs| where Vs is stopping potential versus frequency f of the incident radiation. State how will you use this graph to determine the value of Planck's constant?
A police van moving on a highway with a speed of 30 km/h fires a bullet at a thief's car speeding away in the same direction with a speed of 192 km/h. If the muzzle speed of the bullet is 150 m is, with what speed does the bullet hit the thief's car?
According to Einstein's photoelectric equation, the plot of the kinetic energy of the emitted photoelectrons from a metal Vs the frequency of the incident radiation gives as straight the whose slope:
A 200 W sodium street lamp emits yellow light of wavelength 0.6 µm. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is:
Einstein work on the photoelectric effect provided support for the eqn:-
If the frequency of light in a photoelectric experiment is double the stopping potential will
If the energy of photon corresponding to a wavelength of 6000 A° is 3.32 × 10−19 J, the photon energy for a wavelength of 4000 A° will be ______.
The slope of frequency of incident light and stopping potential for a given surface will be
What will be wavelength of a photon of momentum 6.6 × 10–24 kgms–1?
Which of the following is/are true for cathode ray
The emission of electron is possible
How does stopping potential in photoelectric emission vary if the intensity of the incident radiation increases?
How does stopping potential in photoelectric emission vary if the frequency of incident radiation decreases?
