Atoms Test - 77...

Choose the correct statements for hydrogen and deuterium atoms ( considering motion of nuclie as )

According to the Bohr's theory of hydrogen atom, the speed of the electron, its energy and the radius of its orbit varies with the principal quantum number n, respectively, as:

In Rutherford experiments on $$\alpha$$- ray scattering the number of particles scattered at $${90}^{o}$$ be $$28$$ per minute. Then the number of particles scattered per minute by the same foil, but at $${60}^{o}$$ is

If the radius of Bohr's second orbit of hydrogen atom is $$\alpha$$ then the radius of the $$4^{th}$$ Bohr orbit in atom with Z=3, is

Hydrogen atom is excited from ground state to another state with principal quantum number equal to $$4$$. Then the number of spectral lines in the emission spectra will be :

The radius of the first orbit of hydrogen atom is equal to the radius of the

Suppose an electron is attracted towards the origin by a force $$k/r$$ where $$'k'$$ is a constant and $$'r'$$ is the distance of the electron from the origin. By applying Bohr model to this system, the radius of the $$nth$$ orbital of the electron is found to be $$'rn'$$ and the kinetic energy of the electron to be $$Tn$$. Then which of the following is true?

A particle of mass $$m$$ moves in a circular orbit in a central potential field $$U(r)=\dfrac { 1 }{ 2 } kr^2$$. If Bohr's quantization condition is applied, radii of possible orbitals and energy levels vary with quantum number $$n$$ as:

If element with principal quantum number $$n > 4$$ were not allowed in nature, then the number of possible elements would be 

A certain dye absorbs light of $$\lambda =4000\overset { \circ  }{ A } $$ and emits fluorescent light of $$\lambda =5000\overset { \circ  }{ A } $$. Assuming that under given condition 50% of the absorbed energy is re-emitted out fluorescence, Calculate the ratio of the number of quanta emitted out to the number of quanta absorbed :