Physics Test - ...

The wavelength of $K_{\alpha }$ line in copper is $1.54 A$. The ionization energy  of $K$-electron in copper is:

A proton, a deuteron and an alpha particle, with the same kinetic energy, enter a region of uniform magnetic field B at right angles to the field. What is the ratio of the radii of their circular paths?

Electrons at a certain energy level $(n = n_1)$ can emit $3$ spectral lines. When they are in another energy level, $n = n_2$, they can emit $6$ spectral lines. The orbital speeds of the electrons are in the ratio.

According to Bohr's theory of hydrogen atom, the radii $r$ of stationary electron orbits are related to the principal quantum number $n$ as:

The ionization potential of a hydrogen atom is $13.6 eV$. Its energy in $n = 2$ energy state is:

According to Bohr's theory, the energy of an electron in the $n^{th}$ orbit of an atom of atomic number $Z$ is proportional to:

The electron in a hydrogen atom makes a transition n₁$\to$n₂, where n₁ and n₂ are the principal quantum numbers of two states. Assume Bohr's model to be valid. The time period of the electron in the initial state is eight times that in the final state. What can be the possible values of n₁ and n₂?

A hydrogen-like atom (atomic number $Z$) is in a higher excited state of quantum number $n$. The excited atom can make a transition to the first excited state by successively emitting two photons of energies $10.2 eV$ and $17.0 eV$. Alternately, the atom from the same excited state can make a transition to the second excited state by successively emitting two photons of energies $4.25 eV$ and $5.95 eV$.
Determine the value of $n$. (Ionisation energy of $H$-atom $= 13.6 eV$)

A proton, when accelerated through a potential difference of \(V\) volt, has a wavelength \(λ\) associated with it. An \(α\)- particle, in order to have the same wavelength \(λ\) must be accelerated through a p.d. of:

According to Bohr's theory of hydrogen atom, the total energy of the hydrogen atom with its electron revolving in the $n^{th}$ stationary orbit is: