Advertisements
Advertisements
प्रश्न
Light of wavelength 2000 Å falls on a metal surface of work function 4.2 eV.
What is the kinetic energy (in eV) of the fastest electrons emitted from the surface?
Advertisements
उत्तर
λ = 2000 Å = (2000 × 10-10)m
Wo = 4.2eV
h = 6.63 × 10-34 JS
Using Einstein's photoelectric equation
K. E. = (6.2 – 4.2) eV = 2.0 eV
APPEARS IN
संबंधित प्रश्न
A proton and an α -particle are accelerated through the same potential difference. Which one of the two has greater de-Broglie wavelength Justify your answer.
A proton and a deuteron are accelerated through the same accelerating potential. Which one of the two has the greater value of de-Broglie wavelength associated with it, and Give reasons to justify your answer.
An electron, an alpha particle and a proton have the same kinetic energy.
Which one of these particles has the largest de-Broglie wavelength?
A proton and an electron are accelerated by the same potential difference. Let λe and λpdenote the de Broglie wavelengths of the electron and the proton, respectively.
Find the de Broglie wavelength of electrons moving with a speed of 7 × 106 ms -1.
Describe in brief what is observed when moving electrons are allowed to fall on a thin graphite film and the emergent beam falls on a fluorescent screen.
Answer the following question.
Obtain the expression for the ratio of the de-Broglie wavelengths associated with the electron orbiting in the second and third excited states of the hydrogen atom.
Two bodies A and B having masses in the ratio of 3 : 1 possess the same kinetic energy. The ratio of linear momentum of B to A is:
A strong argument for the particle mature of cathode ray is to
The de-Broglie wavelength (λ) associated with a moving electron having kinetic energy (E) is given by ______.
