Advertisements
Advertisements
प्रश्न
Define the distance of closest approach. An α-particle of kinetic energy 'K' is bombarded on a thin gold foil. The distance of the closest approach is 'r'. What will be the distance of closest approach for an α-particle of double the kinetic energy?
उत्तर
Distance of closest approach
When the alpha particle moves towards the nucleus, it's kinetic energy keeps on decreasing because kinetic energy is being consumed in doing work against the force of repulsion of the nucleus. So the distance from the nucleus at which velocity of the alpha particle becomes zero is known as the distance of closest approach.
Distance of closest approach is given as
`(2Z_e^2)/(4π∈_oK)`
or distance of closest approach prop 1/K
or `r_1/r_2=K_2/K_1`
or `r2 = K_1/K_2×r_1`
`= K/(2K)xxr`
`= r/2`
Hence, the distance of closest approach would be r/2.
APPEARS IN
संबंधित प्रश्न
In the ground state of ____________ electrons are in stable equilibrium, while in ____________ electrons always experience a net force. (Thomson’s model/Rutherford’s model)
Answer the following question, which help you understand the difference between Thomson’s model and Rutherford’s model better.
Keeping other factors fixed, it is found experimentally that for small thickness t, the number of α-particles scattered at moderate angles is proportional to t. What clue does this linear dependence on t provide?
In a Geiger-Marsden experiment, calculate the distance of closest approach to the nucleus of Z = 80, when a α-particle of 8Mev energy impinges on it before it comes momentarily to rest and reverses its direction.
How will the distance of closest approach be affected when the kinetic energy of the α-particle is doubles?
Plutonium decays with half of 24000 years. If plutonium is store for 72000 yrs. The fraction of .its that remain:-
The ratio of the frequencies of the long wave length its of Lyman Balmer series of hydrogen spectrum is
The ratio active Nude 7N13 decays 6C13 through the emission of
Assume that there is no repulsive force between the electrons in an atom but the force between positive and negative charges is given by Coulomb’s law as usual. Under such circumstances, calculate the ground state energy of a He-atom.
What is the nuclear radius of 125Fe, if that of 27Al is 3.6 fermi?
The energy of hydrogen atom in an orbit is −1.51 eV. What are the kinetic and potential energies of the electron in this orbit?
According to Bohr model, magnetic field at centre (at the nucleus) of a hydrogen atom due to motion of electron in the ninth orbit is proportional to:
