41.
The energy levels of a particle of mass m in a potential of the form \[\begin{gathered} V\left( x \right) = \infty ,\,\,\,\,\,\,\,\,\,\,\,\,x \leqslant 0 \hfill \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{1}{2}m{\omega ^2}{x^2},\,\,\,x > 0 \hfill \\ \end{gathered} \]       are given, in terms of quantum number n = 0, 1, 2, 3, . . ., by

42.
The quantum mechanical operator for the momentum of a particle moving in one dimension is given by

43.
$${\bf{\hat A}}$$ and $${\bf{\hat B}}$$ represent two physical characteristics of a quantum system. If $${\bf{\hat A}}$$ is Hermitian, then for the product $${\bf{\hat A\hat B}}$$  to be Hermitian, it is sufficient that

44.
A particle of mass m is confined in an infinite potential well \[V\left( x \right) = \left\{ {\begin{array}{*{20}{c}} {0,}&{{\text{if }}0 < x < L} \\ {\infty ,}&{{\text{otherwise}}} \end{array}} \right.\]
It is subjected to a perturbing potential $${V_P}\left( x \right) = {V_0}\sin \left( {\frac{{2\pi x}}{L}} \right)$$     within the well. Let E(1) and E(2) be the corrections to the ground state energy in the first and second order in V0.
Quantum Mechanics mcq question image
Which of the following is correct?

45.
A particle is incident with a constant energy E on a one-dimensional potential barrier as shown in the figure.
Quantum Mechanics mcq question image
The wave functions in regions I and II are respectively

46.
Which one of the functions given below represents the bound state eigen function of the operator $$ - \frac{{{d^2}}}{{d{x^2}}}$$  in the region, 0 ≤ x < $$\infty $$ , with the eigen value -4?

48.
A parallel beam of infrared radiation of wavelength of 1.01 × 10-6 m is incident normally on a screen with two slits 5 × 10-6 m apart and the resulting interference pattern is observed on a distant screen. What is the largest number of maxima that can be observed on the screen?

49.
A quantum particle of mass m is confined to a square region in XOY-plane whose vertices are given by (0, 0), (L, 0), (L, L) and (0, L). Which of the following represents an admissible wave function of the particle (for I, m, n positive integers)?

50.
A particle has the wave function $$\psi $$ (x, t) = A[exp (iωt) cos (kx)]. Which one of the following is correct?