List of top Nanoelectronics Questions on Solid State Physics, Devices, Electronics

Consider the following statements:
(A) Built-in potential across a diode reduces with increase in temperature.
(B) Electron concentration of n-type semiconductor equals intrinsic concentration at Curie temperature.
(C) Drain current of MOSFET is a positive temperature coefficient (PTC).
(D) Collector current of BJT has a PTC.
Choose the correct statements:

Match List-I with List-II:
 

List-I (Electric field)  List-II (Mobility)
(A) Low electric field(I) Mobility decreases by \( \frac{1}{E} \)
(B) Medium electric field(II) Mobility decreases by \( \frac{1}{\sqrt{E}} \)
(C) High electric field(III) Mobility remains constant

Choose the correct answer:

The unit of ratio of diffusion constant (D) and mobility (\(\mu\)) is:
A silicon crystal is doped with a group III element, the electron concentration falls below intrinsic concentration by a factor of \(10^6\), so the concentration of impurity present is:
Choose the wrong option from the following for the given statement. Statement: Electric field is conservative.
Choose the correct answer from the options given below.
A. \( \vec{\nabla} \times \vec{B} = \mu_0 \vec{J} \) represents Ampere's circuital law.
B. \( \vec{\nabla} \cdot \vec{B} = 0 \) represents magnetic monopole doesn't exist experimentally.
C. \( \vec{\nabla} \times \vec{E} = 0 \) represents the conservative nature of the electric field.
D. \( \vec{\nabla} \times \vec{A} = 0 \) represents the solenoidal condition for a vector field.

Match List-I with List-II
 

List-I List-II 
(A) Faraday’s Law(ii) \( \vec{\nabla} \times \vec{E} = -\frac{\partial \vec{B}}{\partial t} \)
(B) Conservation Law(iii) \( \vec{\nabla} \times \vec{A} = 0 \)
(C) Ohm’s Law(iv) \( \vec{J} = \sigma \vec{E} \)
(D) Gauss’s Law(i) \( \frac{\rho}{\epsilon_0} \)
Gauss's law in magnetostatics is expressed as,
If in a free space, the electric field is given as: \[ \vec{E} = 20 \cos(\omega t - 50x) \hat{y} \, \text{V/m} \] then, the expression of displacement current density \( J_d \) is:
Which of the following statements about hydrogen peroxide is INCORRECT?
In X-ray diffraction, a collimated beam of X-rays, with most appropriate wavelength ranging from .......... is incident on a specimen and is diffracted by the crystalline phases of the specimen:
........... are electromagnetic radiation with typical photon energies in the range of 100 eV to 100 keV:
Measurement of grain size by using X-ray diffraction line broadening can be done by: