List of top Physics Questions asked in Banaras Hindu University Postgraduate Entrance Test

A microcanonical ensemble represents:
Phase space area of a 1-D SHO with mass \(m\), angular frequency \(\omega\) and having energy between \(E\) and \(2E\) is:
The distribution function \( f(E) \) for a photon gas is given by:
Consider a linear collection of \( N \) independent spin 1/2 particles, each at fixed location. The entropy of the system is:
In a radio wave if \(E_0 = 10^{-4} \) V/m, then the magnitude of magnetic field and pointing vector is:
In the TM mode:
The magnetic flux density created by an infinitely long conductor carrying a current \(I\) at a radial distance \(R\) is:
Consider a system of 3 fermions which can occupy any of the 4 available energy states with equal probability. The entropy of the system is:
For a two-dimensional free electron gas, the electron density \(n\) and Fermi energy \(E_F\) are related as:
Partition function for a gas of photons is given as \( Z \propto e^{A T^3} \). The specific heat of photon gas varies with temperature as:
What is the major factor for determining whether a medium is free space, lossless dielectric, loss of dielectric or good conductor?
The work done by the force \( \mathbf{F} = (4\hat{i} -3\hat{j} + 2\hat{k}) \) N in giving a 1 nC charge a displacement of \( (10\hat{i} + 2\hat{j} -7\hat{k}) \) m is:
The dominant mode for rectangular waveguide is:
At cut off the JFET channel is:
The divergence of the vector field \( \mathbf{P} = x^2 y \hat{i} + xyj \) is:
In a waveguide, which condition always holds good?
Radio waves in the frequency range 3 MHz – 30 MHz propagate through which mode of propagation?
A certain transistor is to be operated with \( V_{CE} = 6V \). If its maximum power rating is 250 mW, what is the maximum collector current that it can handle?
A certain JFET has transconductance 4mS with an external AC drain resistance 1.5kΩ, what is the ideal voltage gain?
The circuit shown is used for:
Integration
The correct equivalent symbol for the AND gate with inverted inputs shown below will be:
equivalent symbol for the AND
If the peak rectified voltage from a full-wave rectifier is 15V, the approximate average rectified voltage will be:
The de-Broglie wavelength of a 10 KeV electron is equal to:
The value of \( \frac{1}{r} \) in the \( \psi_{1,0,0}(r,\theta,\phi) \) state of a hydrogen atom is (\( a_0 \) is Bohr radius):
Which of the following is not correct about Pauli spin matrices?