Which of the following statement(s) is/are true for p-type semiconductors?
(A) Holes are minority carriers and pentavalent atoms are the dopants.
(B) Electrons are majority carriers and trivalent atoms are the dopants.
(C) Holes are majority carriers and trivalent atoms are the dopants.
(D) Electrons are minority carriers and trivalent atoms are the dopants.
Choose the correct answer from the options given below:

Electrical energy is transmitted over long distances at high alternating voltages by the use of a transformer. Choose the correct statements from the following :
(A) Higher voltage implies less power loss.
(B) The alternating magnetic flux induces eddy currents in the iron core and causes heating.
(C) Step up transformer increases the current by reducing the voltage in the above transformer.
(D) Transmission lines can be made thinner to reduce power loss.
Choose the correct answer from the options given below :

Which of the following is not a significant characteristic of a pulse?

The forbidden energy gap for Si is

A transformer has 400 turns in the primary coil and 8000 turns in the secondary coil. It is connected to a 220 V main supply. The potential difference per turn in secondary coil is

An infinite plane sheet of charge density \(10^{-8} \text{ C m}^{-2}\) is held in air. In this situation, the distance between two equipotential surfaces, whose potential difference is 10 V, will be (Given: Permittivity of vacuum\(\epsilon_0 \approx 8.85 \times 10^{-12} F / m\))

A sample of HCl gas is placed in an electric field of \(3 \times 10^4 \mathrm{~N} \mathrm{C}^{-1}\). The dipole moment of each HCl molecule is \(6 \times 10^{-30} \mathrm{C} \mathrm{m}\). The maximum torque that can act on this molecule is :

\(\int_2^5|x-3| d x\) equals

Read the passage carefully and answer
When a metal is placed in a solution of its ions, the metal can lose electron and can go in the solution as ion or the metal ion in the solution can take electron from the electrode and get deposited as metal. Thus, the electrode acquires either positive or negative charge with respect to the solution leading to the development of a potential difference between the metal electrode and the solution. This potential difference is called the electrode potential of the metal. The electrode potential of a metal is a measure of relative tendency to undergo oxidation (loss of electron) or reduction (gain of electron). When the concentration of the ions in the solution is unity, the electrode potential is called standard electrode potential. The magni of potential depends upon the nature of electrode, concentration of ions in solution and the temperature. In a galvanic cell, the electrode at which oxidation occurs is known as anodic half-cell and the electrode at which reduction occurs is known as cathodic half cell. The emf of the cell in terms of standard reduction potential is given by \(E_{\text {cell }}^{\circ}=E_{\text {cathode }}^{\circ}-E_{\text {anode. }}^{\circ}\).The standard free energy change of the redox reaction taking place in the cell is related to \(E_{\text {cell }}^{\circ}\) by \(\Delta G^{\circ}=-n F E^{\circ}\). A redox reaction would occur spontaneously if the free energy change is negative. The equilibrium constant of the reaction is related to the standard free energy change by \(\Delta G^{\circ}=-R T \ln K\).
The equillibrium constant of a feasible cell reaction is

Which of the following shows the correct relation between electric Intensity \(E\), and electric potential \(V\) :

Which of the following complexes will show absorbance of light at the lowest wavelength?

In a diffraction pattern due to a narrow slit of width a, alternate dark and bright fringe pattern is obtained on a screen kept at distance D from the slit. Choose the correct option.
(A) The angular width of central maximum is given by 2D/a, linear width is given by 2D\lambda/a
(B) When the size of aperture, a is quite large, the diffraction effect is negligible,
(C) For light of smaller wavelength, angular width of central maximum increases, while linear width decreases,
(D) Angular width of central maximum does not decrease while linear width decreases on decreasing distance of screen from slit.
Choose the correct answer from the options given below:

The electric field vector oscillates according to the equation \( \vec{E} = 4 \sin [1.8y + (5.4 \times 10^8)t] \hat{k} \). The equation of magnetic field vector is: